Term
| SEVERAL BRANCHES OF ANATOMY |
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Definition
BRANCH OF ANATOMY
Embryology: The first eight weeks of development after fertilisation of a human egg.
Developmental Biology: The complete development of an individual from fertilisation to death.
Cell biology: Cellular structure and functions.
Histology: Microscopic structure of tissues.
Gross anatomy: Structures that can be examined without a microscope.
Systemic anatomy: Structure of specific systems of the body such as the nervous or respiratory systems.
Regional anatomy: Specific regions of the body such as the head or chest.
Surface anatomy: Surface markings of internal anatomy through visualisation and palpation (gentle touch).
Imaging anatomy: structures that can be visualised using X-Rays, MRI's CT Scans,ect
Pathological Anatomy: structual changes associated with disease. |
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Term
| SEVERAL BRANCHES OF PHYSIOLOGY |
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Definition
Neurophysiology: Functional properties of nerve cells.
Pathophysiology: Functional changes associated with disease and ageing.
Endocrinology: Hormones (chemical regulators in the blood and how they control body functions)
Cardiovascular physiology: Functions of the heart and blood vessels.
Immunology: The body's defenses against disease-causing agents.
Respiratory physiology: the function of the air passageways and lungs.
Renal physiology: Functions of the kidneys.
Exercise physiology: change in cell and organ function due to muscular activity. |
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Term
Medical Science with Martin Introduction to A&P
ANATOMY >
PHYSIOLOGY >
Theory: |
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Definition
STRUCTURE
FUNCTION
The structure of a body often reflects its functions and that's why they're closely related. |
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Term
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Definition
Raspatory
Urinary
Reproductive
Cardiovascular
Nervous
Muscular
Skeletal
Digestive
Endocrine |
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Term
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Definition
*Made up two or more types of tissue
*Tissue is made up many times of the same kinds of cell |
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Term
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Definition
*Cell are the functional units of the body
*Cells are made up of chemicals (atoms and molecules). |
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Term
| LEVELS OF STRUCTURAL ORGANISATION |
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Definition
*Organism
*Organ System
*Organ
*Tissue
*Cellular
*Chemical |
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Term
REDUCTIONISM VS HOLISISM
Bottom Up Vs Top Down |
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Definition
Holisism works from the top down, the body sends neurotransmitters that affects our entire system. For example if we are nervous we might get butterflies in our stomach.
Reductionism being bottom up is more the conventional approach. |
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Term
| 6 BASIC PROCESSES OF LIFE |
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Definition
*Metabolism > Catabolism + Anabolism
*Responsiveness
*Movement
*Growth
*Differentiation> through growth becomes more specialized cells
*Reproduction> |
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Term
HOMEOSTASIS (HOMEO, STATIS)
Homeo: Same
Statis: Still
FEEDBACK/SYSTEM LOOPS TO RETURN TO HOMEOSTASIS: Negative> Effector works in opposite to the stressor and Positive> Effector works to amplify stressor
Same standing still. |
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Definition
*Body temperature a good example of needing to be kept still or at a level that works in a controlled condition.
*Blood pressure. We don't want it too high or too low.
*Blood sugar
*Hormones
*PH
*Fluid levels
*Calcium
*Iron
Everything you do as a natural therapist is to assist your clients in maintaining Homeostasis.
Disruption of Homeostasis > Disease > Signs & Symptoms > Death
Homeostasis is maintained by a Feedback System > Receptor, Control Centre, Effector |
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Term
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Definition
*Anatomical Position: Body faced forward, Palms showing
*Superior (cephalic): Towards head
*Inferior (caudal): Towards toes
*Anterior (aka ventral): Front
*Posterier (aka dorsal): Back
*Medial: anywhere midline
*Lateral: towards the edge, headed away from midline
Intermediate: In-between the two above
*Ipsilateral: two things on one side
*Contralateral: something happening on other side
*Superficial: towards the skin
*Deep: further in the body
*Proximal: closer to hip (top half of body)
*Distal: closer to toes (bottom half of body) for example fingers are distal to the wrist. Distal is further away/going south from another region. |
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Term
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Definition
*Sagittal: organ view/cut into left or right. Centre plan
Midsagittal: view/cut in centre
Parasagittal: view/cut vertical but not completely centred
*Transverse (cross section): horizontal view "transverse plane".
*Frontal (coronal): Front view/crown
*Oblique: combination of views/on an angle
*Oblique |
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Term
BODY CAVITIES
>Lined by Serous Membranes |
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Definition
*Dorsal
>Cranial (brain)
>Vertebral (spinal) canal
*Ventral
>Thoracic; diaphragm >ribcage
*Abdominopelvic >pelvis, skin muscles that surround abdomen
*Parietal layer> serious fluid/superficial/surface
*Visceral layer> deeper, stuck to organs, packaging
Eg. abdominal cavity lined by peritoneum |
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Term
BODY CAVITIES
Thoracic Cavities Contain> |
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Definition
*Pleural cavities> contain the lungs
*Mediastinum> between the sternum and vertebrae; contains heart, thymus, esophagus, trachea, aorta.
*Pericardial cavity> contains heart.
(peri/perimeter/around the heart, which is the "cardial" part in this term. |
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Term
ABDOMINOPELVIC REGIONS AND QUADRANTS
*Divided into 4 quadrants
*Can also be divided into 9 quadrants
(noughts and crosses)
Epigastric region, umbilical region, hypogastric region > then the left and right sections of that region total 9 quadrants |
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Definition
*Can divide abdomen into 4 quadrants; a vertical and horizontal line that intersects at the umbilicus (naval/belly button).
- RLQ (right lower quadrant)
- RUQ (right upper quadrant)
- LUQ (left upper quadrant)
- LLQ (left lower quadrant)
These sections can help determine what organs are being affected. |
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Term
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Definition
| Familiarize yourself with these methods. Do your own research. |
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Term
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Definition
| Homeostasis (hō′-mē-ō-STĀ-sis; homeo- = sameness; -stasis = standing still) is the condition of equilibrium (balance) in the body’s internal environment due to the constant interaction of the body’s many regulatory processes. Homeostasis is a dynamic condition. In response to changing conditions, the body’s equilibrium can shift among points in a narrow range that is compatible with maintaining life. For example, the level of glucose in blood normally stays between 70 and 110 milligrams of glucose per 100 millilitres of blood. * Each structure, from the cellular level to the system level, contributes in some way to keeping the internal environment of the body within normal limits. |
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Term
AAP101 LESSON 4: THE CHEMICAL LEVEL OF ORGANISATION
Atoms, Elements, Compounds |
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Definition
Elements of the human body
So, the key points you have learnt so far are:
The different types of matter that exist are made up of elements.
Elements are made up of atoms.
An element, by its definition, only contains one type of atom. Hydrogen is made up of hydrogen atoms. Oxygen is made up of oxygen atoms.
If a substance contains more than one type of atom, it is called a compound. It is composed of two or more elements.
Atoms of the same element are all pretty much the same*. Atoms from different elements will be different sizes. |
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Term
THE BODY IS MADE UP OF 4 ELEMENTS
These are called the major elements of the body. |
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Definition
*Oxygen
*Carbon
*Hydrogen
*Nitrogen
This makes up 96% of our body, the other 4% are trace elements.Example bones and teeth. A varied diet is important to maintain health. |
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Term
LESSON 4: HOW MATTER IS ORGANISED
Chemical Reactions |
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Definition
*A bond, in chemistry, is a joining together of atoms.
*Whenever atoms form new bonds or break old bonds, a chemical reaction is taking place.
*The substances that enter into a reaction are called reactants. The resulting substances of a reaction are called the products.
*The first type of chemical reaction is called a synthesis reaction. A synthesis reaction simply involves joining together of reactants to make a larger product.
*Remember that a ‘chemical’ consists of millions of atoms.
*The substances that enter into a reaction are called reactants. The resulting substances of a reaction are called the products>The opposite kind of reaction is decomposition.
A synthesis reaction simply involves joining together of reactants to make a larger product.
*When atoms break their bonds, this is 'decomposition'. Atoms don't decompose individually as they are the smallest unit of an element.
*An 'exchange reaction is a combination of synthesis and decomposition. They exchange places with each other just like in ballroom dancing.
*'Reversible' reaction, can go back and forth in both directions. Can be formed, broken, then formed again. |
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Term
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Definition
*Metabolism is the sum of all chemical reactions occurring in your body.
*In Anatomy and Physiology, synthesis
reactions are called Anabolic reactions. Anabolism is "building up"; synthesis reaction is the foundation to building upward. For example anabolic steroids building up muscle.
*Decomposition reactions in the body are called catabolic. Catabolism is breaking down.
*Metabolism = catabolism + anabolism.
*Fast or slow metabolism is purely speed related but a fast metabolism would have more chemical reactions than a slow one.
*Simply being alive consumes energy. We need food to create energy. Those with a faster metabolism consume more energy.
* |
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Term
| TYPES OF CHEMICAL REACTIONS |
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Definition
After a chemical reaction takes place, the atoms of the reactants are rearranged to yield products with new chemical properties.
*When two or more atoms, ions, or molecules combine to form new and larger molecules, the processes are called synthesis reactions. The word synthesis means ‘to put together’. A synthesis reaction can be expressed as follows.
All of the synthesis reactions that occur in your body are collectively referred to as anabolism
Decomposition reactions split up large molecules into smaller atoms, ions, or molecules. A decomposition reaction is expressed as follows.
Many reactions in the body are exchange reactions; they consist of both synthesis and decomposition reactions.
Some chemical reactions proceed in only one direction, from reactants to products, as previously indicated by the single arrows. Other chemical reactions may be reversible. In a reversible reaction, the products can revert to the original reactants. A reversible reaction is indicated by two half-arrows pointing in opposite directions.
Oxidation refers to the loss of electrons; in the process the oxidised substance releases energy. Reduction refers to the gain of electrons; in the process the reduced substance gains energy. Oxidation–reduction reactions are always parallel; when one substance is oxidised, another is reduced at the same time. |
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Term
LESSON 5: THE PLASMA MEMBRANE
Subheading - WHAT IS A CELL |
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Definition
*our body is made up of systems, which are made up of organs, which are made up of tissues, which are made up of cells, which are made up of atoms/molecules/compounds.
If you were to break the body down into the smallest pieces that still retained the characteristics of your body, you’d be left with cells. Cells are therefore sometimes referred to as the functional unit of life.
*Each of your cells is like a miniature version of you. |
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Term
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Definition
*Plasma Membrane; forms the cell’s flexible outer surface
*The cytoplasm (SĪ-tō-plasm; -plasm = formed or moulded) consists of all the cellular contents between the plasma membrane and the nucleus
within the cytoplasm are different forms of organelles
*The nucleus (NOO-klē-us = nut kernel) is a large organelle that houses most of a cell’s DNA |
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Term
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Definition
*The body of an average human adult is composed of nearly 100 trillion cells
*All of these cells can be classified into about 200 different cell type
*The sizes of cells are measured in units called micrometres (mĪ-KROM-i-ters). One micrometre is equal to 1 one-millionth of a metre.
*The shapes of cells vary. A cells shape is related to its function in the body.This change in shape allows groups of smooth muscle cells to narrow or widen the passage for blood flowing through blood vessels.In this way, they regulate blood flow through various tissues. |
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Term
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Definition
| Recall that some cells contain microvilli, which greatly increase their surface area. Microvilli are common in the epithelial cells that line the small intestine, where the large surface area speeds the absorption of digested food. Nerve cells have long extensions that permit them to conduct nerve impulses over great distances. As you will see in the following chapters, cellular diversity also permits organisation of cells into more complex tissues and organs. |
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Term
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Definition
Cell Membrane;
- Structure
- Permeability
> Transport across to cell membrane
- The joining of systems; Organism |
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Term
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Definition
Digestive, Reproductive, Muscular system etc.
- Systems are made up of organs, which are made up of tissue
- Tissue is made up of cells
- Cells are made up of chemicals; atoms, molecules, etc |
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Term
| STRUCTURAL LEVELS OF ORGANISATION |
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Definition
- ORGANISM
- SYSTEM
- ORGAN
- TISSUE
- CELLULAR
- CHEMICAL |
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Term
| WHAT IS THE STUDY OF CELLS CALLED? |
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Definition
CYTOLOGY
E.G OSTEOCYTE - Cells of the bone |
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Term
THE CELL MEMBRANE
INTRODUCTION TO CELLS |
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Definition
*The "functional unit of life"
*Each cell is a mini version of you
*Each cell is alive, can watch it move
*Each cell shares nutrients, produces waste etc
*Brain is made up of brain cells
*Muscle is made up of muscle cells |
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Term
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Definition
*A cell can be divided into different components
*Cell membrane can be thought of as the "skin" of the cell
*The cell membrane separates the inside of the cell from the outside. |
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Term
THE PHOSPHOLIPID BILAYER
3.2 PLASMA MEMBRANE |
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Definition
*A flexible yet sturdy barrier surrounds and contains the cytoplasm of a cell. "Fluid mosaic model"
*Plasma membrane represents a continuous sea of fluid that contains a mosaic of different proteins.
*Some proteins float freely like icebergs, some are more anchored in specific locations.
*Some proteins allow movement, some signal like receptors that link the plasma/skin into either intracellular or extracellular proteins. |
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Term
| FIGURE 3.2 FUNCTIONS OF THE PLASMA MEMBRANE |
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Definition
1. Acts as a barrier separating inside and outside of the cell
2. Controls the flow of substances into and out of the cells
3. Helps indentify the cell to other cells. (eg immune cells)
4. Participates in intercellular signaling |
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Term
3.2 STRUCTURE OF THE PLASMA MEMBRANE
THE LIPID BILAYER |
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Definition
*Basic structural framework of the plasma membrane is the lipid bilayer
*TWO back to back layers made up of three types of lipid molecules; phospholipids, cholesterol, glycolipids
*About 75% of the membrane lipids are phospholipids; lipids that contain phosphorus.
*Present in smaller amounts; Cholesterol (hydroxol/OH) 20% and glycolipids 5% (Carbohydrate group)
*Bilayer arrangement is in two parts; polar and non-polar = amphipathic |
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Term
| POLAR VS NON POLAR "AMPHIPATHIC" |
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Definition
The polar part is HYDROPHILLIC (Hydro = water, phillic = loving).
The non-polar is HYDROPHOBIC (Hydro = water, Phobic = fearing) |
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Term
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Definition
*Weakly Amphipathic
*The stiff steroid rings of cholesterol are non-polar and fit among the fatty acid tails of the phospholipids and glycolipids. |
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Term
| THE CELL MEMBRANE - Lecture |
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Definition
*Extracellular fluid - extraordinary/outer fluid that is outside of the cells
*Intracellular fluid - fluid that is inside the cell |
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Term
CELL MEMBRANE Subtopics
- AKA Plasma Membrane
- Fluid Mosaic Membrane
- Phospholipid Bilayer (Bilayer meaning 2 layers)
- Amphipathic; both polar + non-polar |
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Definition
*Phospholipid - Made up of phosphorous and fatty acids.
* Polar> Electrically Charged
* Non Polar> Neutral
*Cell Membrane;
PROTEINS floating in a sea of Phopholipids
CHOLESTEROL, also part of cell membrane
Our body makes cholesterol and is essential
CHOLESTEROL adds strength and stability to our cell membrane
DIAGRAM - Phosphate heads are circles, Fatty acid tails are attached to those circles. |
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Term
PHOSPHOLIPIDS;
*Phosphate heads are... |
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Definition
POLAR> electrically charged
HYDROPHILIC> (Hydro = water, Philic = Loving) |
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Term
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Definition
NON-POLAR> Non Electrical
HYDROPHOBIC> Water fearing |
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Term
MEMBRANE PROTEINS
*Intergral (transmembrane) proteins
*Surafec (peripheral) proteins> Glycoproteins; sugar molecule attached (glucose) |
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Definition
FUNCTIONS:
1) Ion Channels (tunnel ions, which can pass over)
2) Transporter proteins (changing shape to transfer)
3) Receptors for ligands (sending a message to the cell) Ligands; binds receptors
4) Enzymes (speeds up chemical reactions)
5) Linker proteins (helps link everything togather).
6) Cell identity markers (incl MHC proteins) Proteins displayed checks identity to make sure it belongs. EG organ transplant; immune system can't identify new cells, then attacks itself. (SUMMARY IN TEXT BOOK) |
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Term
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Definition
A substance may be
> water soluable (eg sugar/salt)
> lipid soluable (oil; dissolves in fat)
Solute = dissolved substance (eg salt)
Solvent = the medium in which a substance is dissolved (eg water) |
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Term
| PERMEABILITY > Whether a substance will be allowed to pass through |
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Definition
MEMBRANE PERMEABILITY
"Selectively permeable"
Permeable to:
*NON POLAR, HYDROPHOBIC substances eg LIPID GASES
*Impermeable to
POLAR, HYDROPHILIC SUBSTANCES eg Ions, glucose; but is permeable to water molecules alone. |
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Term
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Definition
GRADIENT = Steepness
CONCENTRATION GRADIENT = more of something in one place, less in another. The greater the difference in concentrations, the greater the gradient. |
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Term
| WHAT NATURALLY OCCIRS WHEREVER A CONCETRATION GRADIENT EXITSTS? WHAT DOES NATURE AIM FOR? |
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Definition
| EQUALISATION / EQUALIBRIUM |
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Term
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Definition
Substances will naturally move down their concentration gradient, from an area of high concentration to low concentration, until equilibrium is reached.
*There exists on either side of the cell membrane > an electro-chemical concentration |
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Term
TRANSPORT PROCESSES SUMMARY
Across the cell membrane... |
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Definition
PASSIVE
>Diffusion
>Simple
>Facilitated
>Carrier meditated
>Osmosis
ACTIVE
>Primary active transport
>Secondary active transport
>Vesicular
>Exocytosis
>Endocytosis; Phagocytosis, Pinocytosis. |
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Term
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Definition
>Diffusion = movement of a solute down its concentration gradient
AFFECTED BY:
- Steepness
- Temperature
- Mass of solute
- Surface area
- Diffusion Distance
>Osmosis = the movement of water, across a selectively permeable membrane, due to a difference in the concentration of solutes (permeable to an area).
Transport Process;
*Think of diffusion as the movement of a solute down its concentration gradient.
* In osmosis its water that does the moving
*Water is moving down its concentration gradient due to its difference in the concentration solutes
*The solutes cannot move across the membrane, but water can
(OSMOSIS DIAGRAM) (ELECTRON MICROGRAPHS) |
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Term
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Definition
>ACTIVE
Primary active transport - directly uses ATP to move a substance against its concentration gradient. (ATP is an energy currency)
Cell membrane pushes sodium out and brings potassium in> hydration. Moves down concentration gradient. This is where ATP comes in. We use a lot of energy to do this. |
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Term
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Definition
ACTIVE
> PRIMARY ACTIVE TRANSPORT
>SECONDARY ACTIVE TRANSPORT - indirectly uses ATP to move a substance against its concentration gradient.
SYMPORTERS; move in same direction
ANTIPORTERS; move in opposite direction |
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Term
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Definition
VESICULAR - Container inside cell
EXOCYTOSIS - exo; outer, CYT cell, OSIS; happening
ENDOCYTOSIS - receptor meditated endocytosis; phagocytosis (eats something) and pinocytosis (drinks something) |
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Term
| LESSON 6: THE NUCLEUS AND CYTOPLASM |
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Definition
CYTOSOL: Watery substance (gel-like) that makes up the 'body' of the cell
CELLS ORGANS: "Organelles" are embedded with Cytosol |
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Term
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Definition
*Intracellular fluid
*Fluid portion that surrounds organelles
*55% of the total cell volume
*75%-90% of water (plus dissolved and suspended components); different types of ions, glucose, amino acids, proteins, lipids, ATP, waste products. Also organic molecules that aggregate into masses for storage. These aggregations appear/disappear at different times in the life of a cell. eg lipid droplets which contain TRIGLYCERIDES, CLUSTERS OF GLYCOGEN molecules called GLYCOGEN GRANULES. |
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Term
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Definition
*The cytosol is the site for many chemical reactions required for a cells existence.
*Provides building blocks for maintenance of cell structures and for cell growth. |
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Term
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Definition
*A network of protein filaments that extends throughout the cytosol.
*contributes to cytoskeletons structure well as organelles structure.
*their diameter is increased by MICROFILAMENTS, INTERMEDIATE FILAMENTS and MICROTUBULES. |
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Term
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Definition
*The thinnest elements of the cytoskeleton. Composed of proteins "ACTIN + MYOSIN" - prevalent at the edge of a cell.
*They have two general functions: generating movement and mechanical support.
*Involved in muscle contraction
*Cell division
*cell locomotion
*Occurs during the migration of embryonic cells during development, invasion of tissues by white blood cells to fight infection or migration of skin cells during wound healing. |
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Term
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Definition
*are the anchor for cytoskeleton to integral proteins in the plasma membrane (cell membrane)
*provides chemical support for the MICROVILLI (small tufts of hair)
MICROVILLI are abundant on cells involved in absorption, such as epithelial cells that line the small intestine. |
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Term
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Definition
ACTIVE
>Primary Active Transport
>Secondary Active Transport
Indirectly uses ATP to move a substance against its concentration gradient
- Symporters; move in same direction
- Antiporters; move in opposite direction |
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Term
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Definition
VESICULAR; container inside cell
EXOCYTOSIS; EXO = Outer/CYT = Cell/OSIS = Happening)
ENDOCYTOSIS; Receptor Meditated Endocytosis
- Phagocytosis (eats something)
- Pinocytosis (drinks something) |
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Term
| LESSON 6: THE NUCLEUS & CYTOPLASM |
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Definition
CYTOSOL; Watery substance (gel-like) makes up 'body' of the cell
CELLS ORGANS = Organelles are embedded within the cytosol
CYTOSOL; Intracellular fluid
Fluid portion that surrounds organelles.
It is 55% of total cell volume.
It is 75-90% water.(plus dissolved and suspended components) |
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Term
| LESSON 6: THE NUCLEUS & CYTOPLASM |
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Definition
CYTOSOL: Site for many chemical reactions required for a cells existence.
- provides building blocks for maintenance of cell structures and for cell growth. |
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Term
LESSON 6: THE NUCLEUS & CYTOPLASM
CYTOSKELETON |
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Definition
- Network of protein filaments
- contributes to cytoskeleton structure as well as organelles structure
- diameter is increased by microfilaments, intermediate filaments and microtubules |
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Term
LESSON 6: THE NUCLEUS & CYTOPLASM
MICROFILAMENTS |
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Definition
- Thinnest elements of the cytoskeleton. Composed of proteins ACTIN + MYOSIN - prevalent at the age of a cell
- two general functions; generating movement and mechanical support
- involved in muscle contraction
- cell division
- cell locomotion
- occurs during migration of embryonic cells during development/ivasion/migration of cells during wound healing |
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Term
LESSON 6: THE NUCLEUS & CYTOPLASM
MICROFILAMENTS FOR CYTOSKELETON |
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Definition
- Microfilaments are the anchor for cytoskeleton to integral proteins in the plasma membrane
- provides chemical support for microvilli (small tufts of hair)
MICROVILLI
> abundant on cells involved in absorption such as epithelial cells that line the small intestine |
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Term
LESSON 6: THE NUCLEUS & CYTOPLASM
MEDICAL SCIENCE WITH MARTIN
ORGANELLES |
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Definition
STRUCTURAL LEVELS OF ORGANISATION:
- Organism
- System
- Organ
- Tissue
CELLULAR:
> Nucleus
> Cytoplasm; Cytosol; Organelles
> Cell membrane
CHEMICAL |
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Term
LESSON 6: THE NUCLEUS & CYTOPLASM
What is the word for cell? |
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Definition
CYTOPLASM (CYTO = CELL)
CYTOPLASM "fluid of cell"
"Site"
CYTOPLASM is a container for organelles and cytosol |
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Term
LESSON 6: THE NUCLEUS & CYTOPLASM
CYTOSKELETON |
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Definition
3 TYPES OF PROTEIN FILAMENTS
> MICROFILAMENTS = enable movement of a cell and mechanical support
> INTERMEDIATE FILAMENTS = strength and structure
> MICROTUBULES = shape and movement |
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Term
LESSON 6: THE NUCLEUS & CYTOPLASM
CENTROSOME |
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Definition
CENTROSOME
> Assisting in cell division |
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Term
LESSON 6: NUCLEUS & CYTOPLASM
ORGANELLES FROM TEXTBOOK |
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Definition
TEXTBOOK;
- Specialised structures within a cell
- Characteristic shapes
- perform functions for cell growth, maintenance and reproduction
- minimal interference among reactions as they are confined to different organelles
- each type of organelle has a different set of enzymes > they have their own specific biochemical processes/reactions |
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Term
LESSON 6: NUCLEUS & CYTOPLASM
CENTROSOME FROM TEXTBOOK |
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Definition
CENTROSOME
- Located near nucleus
Consists of 2 components; centrioles and pericentriolar material > cylindrical structures
> they contain 9 clusters of 3 microtubules inside them (triplets) arranged in circular pattern
> PERICENTRIOLAR contains hundreds of ring shaped complexes composed of protein "tubulin"
TUBULIN
- Organising centres for growth of the mitotic spindle; plays important role in cell dividing and non diving cells |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
CENTROSOME |
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Definition
| - During cell division, centrosomes replicate so succeeding generations of cells have capacity for cell division |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MEDICAL SCIENCE WITH MARTTIN |
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Definition
ORGANELLES
CENTROSOME
> pair of centrioles
each centriole consists of 9 clusters of 3 microtubules
> pericentriolar material
Tubulin
Centrosome is made up of 2 centrioles > function; cell division
(end of lecture) |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
CILIA AND FLAGELLA |
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Definition
CILIA
- like hairs on the surface of a cell
- act to move substances across surface of cell
FLAGELLA
- Like tails that act to move the cell itself |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MICROTUBULES |
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Definition
MICROTUBULES
- Dominant components of cilia and flagella, motile projections of the cell surface
CILIA; numerous, short hair like projections that extend from surface of a cell
- Each cilia contains a core of 20 milion microtubules surrounded by plasma membrane
MICROTUBULES arranged as a pair in the centre surrounded by 9 clusters of 2 fused microtubules (doublets) |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
CILIA |
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Definition
CILIA - each cilia is anchored by a basal body just below surface of plasma membrane
- basal body; similar structure to centriole and initiates assembly of cilia and flagella. |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MEDICAL SCIENCE WITH MARTIN |
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Definition
CILIA
- like hairs on a cell
- more a substance across the surface of a cell
- examples; respiratory tract (cilia escalator), uterine tissues.
FLAGELLA
- movement of sperm cell
- tail
- some bacteria has flagella
RIBOSOMES
- important cellular machinery; synthesise proteins
- ribonucleic acid (ribosomal rna or rRna)
- each ribosome includes more than 50 proteins
- each ribosome consists of 2 subunits, one half the size of the other.
- subunits made separately in nucleolus; a spherical body inside nucleus
- once subunits produced, they exit nucleus separately, then come together in cytoplasm > see diagram 3.18 in textbook |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MEDICAL SCIENCE WITH MARTIN |
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Definition
RIBOSOMES
- sites of protein synthesis in the cell
- consists of 2 subunits, like a pair of hands clasping together
- may appear in cytosol or attached to
ENDOPLASMIC RECTICULUM
- two types fo ER, rough and smooth
- rough ER contains ribosomes (which make it look rough)
- smooth ER does not contain ribosomes |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
TEXTBOOK + MEDICAL SCIENCE WITH MARTIN |
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Definition
ENDOPLASMIC RETICULUM
TEXTBOOK
ENDOPLASMIC > means cytoplasm network
- network of membranes in the form of flattened sacs of tubules
- ER extends from the nuclear envelope (membrane around nucleus) to which it is connected and projects throughout the cytoplasm
LECTURE:
ENDOPLASMIC RETICULUM:
ROUGH ER
> has ribosomes attached to it
> synthesises proteins
> extends from nucleus
SMOOTH ER
> No ribsosomes
> synthesises fats, role in detoxification
> extends from rough ER
"endo" - inside, "plasmic" = cytoplasm, "reticulum' = network |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MEDICAL SCIENCE WTIH MARTIN
GOLGI COMPLEX |
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Definition
GOLGI COMPLEX:
- Looks like a stack of pita bread
- modifies, sorts and packages proteins; dispatches them to different areas of the cell, or for exit from the cell
- proteins may be packaged into secretory vesicles |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
GOLGI COMPLEX
TEXTBOOK |
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Definition
- most of proteins synthesised by ribosomes attached to the ER are transported to other regions of the cell
- first step of transport pathway is through organelle GOLGI COMPLEX.
- consists of 3 to 20 cistemae (singular cavities); small, flattened membranous sacs with buldging edges that resemble a stack of pita bread
- Golgi complex often curved, cup like shape
- most cells have golgi complexes
- more extensive in cells that secrete proteins due to organelles role in cell. |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
LYSOSOMES/PEROXISOMES/PROTEASOMES |
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Definition
- 3 Organelles with similar names and similar functions all differing slightly
LYSOSOMES
Lysosomes "lyso" dissolving, "somes" bodies
- membrane enclosed vesicles that form the golgi complex
- contains kinds of powerful digestive and hydrolytic enzymes
- break down wide variety of molecules once lysosomes fuse with vesicles found during endocytosis
- lysosomal enzymes work best as an acidic PH
- Membrane includes active transport pumps
- imports hydrogen IONS (H+)
- lysosomal interior has a PH of 5 which is times more acidic than the PH of cytosol (PH 7)
- moves final products of digestion such as glucose, fatty acids and amino acids, into the cytosol (see figure 3.22 in textbook) |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
LYSOSOMES CONTINUED |
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Definition
- lysosomes help recycle worn out cell structures
- lysosomes can engulf another organelle, digest it and return the digested components to the cytosol for reuse
- old organelles are continually replaced
- worn out organelles that are digested = AUTOPHAGY (AUTO = SELF, PHAGY = EATING)
- organelle to be digested is enclosed by a membrane derived from the ER to create vesicle called AUTOPHAGOSOME > vesicle fuses with lysosome |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
LYSOSOMES CONTINUED ; AUTOPHAGY ; AUTOLYSIS |
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Definition
- autophagy is also involved in cellular differentiation, control of growth, tissue re-modelling, adaptation to adverse environments and cell defence
- lysosome enzymes may also destroy entire cell that contains them > process = AUTOLYSIS
- AUTOLYSIS > occurs in some pathological conditions, responsible for the tissue differentiation that occurs immediately after death
- most lysosome enzymes act WITHIN a cell
some operate in extracellular digestion eg fertilisation; head of sperm releases lysosome enzymes aiding penetration of the oocyte (egg) dissolving protective coating = process is ACROSOME reaction (section 29.1 in textbook) |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
PEROXISOMES |
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Definition
- peroxisomes is oxidisation/removal
- smaller than lysosomes
- peroxi = peroxide; somes = bodies
- also called microbodie; contain several oxidases, enzymes that contain oxidise > remove hydrogen atoms from various organis substances eg amino acids and fatty acids are oxidised in peroisomes as a part of normal metabolism
- enzymes in peroxisomes oxidise toxic substances such as alcohol; peroxisomes are very abundant in the liver |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
PEROXISOMES CONTINUED |
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Definition
- byproduct of oxidization reactions is hydrogen peroxide (H2 o2)n
- hydrogen peroxide potentially toxic compound, associated free radicals such as superoxide
- peroxisome also contains enzyme CATALASE which decomposes hydrogen peroxide
-production of H2 02 and degradatin occur in the same cell
- peroxisomes protect other parts of the cell from toxic effects pf the h2 02
- peroxisomes destroy superoxides |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
PEROXISOMES CONTINUED |
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Definition
- without peroxisomes, by products of metabolism could accumulate inside a cell and result in cellular death
- peroxisomes can self-replicate
- new peroxisomes can form from pre existing cells by enlarging and diving
-peroxisomes can be created by components accumalating at a site in the cell and then assemble |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
PROTEASOMES |
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Definition
- PROTEASOMES = protein bodies
- continues destruction of uneeded, damaged or fault proteins in the function of tiny barrel-shaped structures, consisting of four-stacked proteins around a central core
- proteins part of metabolic pathways need to be degraded after completing their function
- protein destruction > negative feedback > halts pathway once appropriate response is achieved
- a typical body cell contains thousands of proteasomes, in both cytosol and nucleus
- proteasomes named after myria proteases enzymes that cut proteins into small peptides
- once enzymes of proteasome have chopped protein into smaller chunks, other enzymes break down the peptides into amino acids, which can be recycled into the new proteins |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MEDICAL SCIENCE WITH MARTIN
ORGANELLES IN POINT FORM |
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Definition
LYSOSOMES
- like little mobile waste disposal units
- contain powerful digestive enzymes
- breakdown anything in the cell that is not needed anymore
PEROXISOMES
- also destroy unwanted substances in the cell, through oxidation
> example of metabolism of alcohol |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MEDICAL SCIENCE WITH MARTIN
ORGANELLES IN POINT FORM |
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Definition
PROTEASOMES
- contain proteases; enzymes that breakdown proteins
- these organelles all need energy to function and come in the form of ATP (energy currency) |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MEDICAL SCIENCE WITH MARTIN
ORGANELLES IN POINT FORM |
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Definition
PROTEASOMES
- contain proteases; enzymes that breakdown proteins
- these organelles all need energy to function and come in the form of ATP (energy currency) |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
TEXTBOOK
MITOCHONDRIA |
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Definition
-plays a crucial role in our physiology
- generate most of the ATP through aerobic (oxygen requiring) respiration
- MITOCHONDRIA (MITO = THREAD, CHONDRIA = GRANULES
- singular is MITOCHONDRION > referred to 'powerhouses' of the cell
- a cell may have as few as a hudnred or as many as several thousand mitochondria, depending on its activity
- cells that use ATP at a high rate such as muscles, liver, kidney, have the most mitochondria
-regular exercise can lead to an increased amount of mitochondria in muscle cells to function more efficiently
- mitochondria located in cell where oxygen enters cell or where ATP is used eg among contractile proteins in muscle cells |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
TEXTBOOK
MITOCHONDRION |
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Definition
- consists of an outer mitochondrial membrane and an inner mitochondrial membrane with a small fluid-filled space between them (both similar to plasma membrane) fig 3.23 in textbook
- inner mitochondrial membrane contains series of folds called mitochondrial cristae (ridges)
- mitochondrial matrix > central fluid cavity of a mitochondrion, enclosed by inner mitochondrial membrane
- elaborate folds of cristae provide enormous surface area for chemical reactions > part of aerobic phase of cellular respiration > reactions that produce most of ATP |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
TEXTBOOK
MITOCHONDRION CONTINUED |
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Definition
- enzymes that catalyse these reactions > located on cristae and in mitochondrial matrix
- mitochondria also plays an important role in APOPTOSIS = A falling off
> the orderly, genetically programmed death of a call
> responses to large numbers of destructive - free radicals, DNA damage, growth factor deprivation, or lack of oxygen/nutrients, certain chemicals are released from mitochondria following formation in the outer mitochondrial membrane |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
TEXTBOOK
MITOCHONDRIA/CYTOCHROME C/RIBOSOMES |
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Definition
- involved in aerobic cellular respiration, also released into the cytosol > includes cascade of activation of protein - digesting enzymes that bring out APOPTOSIS
- like PEROXISOMES, mitochondria self-replicate. Occurs during time of increased cellular energy (ATP) demand or before cell division
- ribosomes; present in mitochondrial matrix synthesis of proteins, occurs in ribosomes
- mitochondria have their own DNA > in form of multiple copies of a circular DNA molecule that contains 37 genes > controls synthesis of 2 ribosomal RNA, 22 transfer RNA; 13 proteins that build mitochondrial components |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
MITOCHONDRIA CONTINUED |
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Definition
- Nucleus of each somatic cell contains genes from your mother and father
- mitochondria genes are only inherited from your mother
- all mitochondria in a cell are descendants of those present in the oocyte (egg) during fertilisation process
- head of sperm lacks more organelles.. any sperm mitochondria are destroyed
- mitochondria dna can be used to trace maternal lineage (to determine if 2 or ore individuals are related; mothers side of family) |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
NUCLEUS |
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Definition
- The most prominent feature of a cell
- spherical / oval shaped structure
- most cells have a singular nucleus
- some don't have a nucleus eg mature red blood cells
- skeletal muscle cells have multiple nuclei
- double membrane called nuclear envelope separates the nucleus from the cytoplasm
- both layers of nuclear envelope are lipid bi-layers; similar to plasma layer
- outer layer of nucleus is continuous with rough er and resembles it in structure
- openings called "nuclear pores" extend through the nuclear envelope |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
NUCLEUS |
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Definition
- each nuclear pore consists of circular arrangement of proteins
> surrounding large central opening
> 10 times wider than pore of a channel protein in the plasma membrane
>figure 3.24 in textbook
- nuclear pores control the movement between the nucleus and the cytoplasm
- small molecules and ions move through the pores by diffusion
- nucleus contains active transport process
> molecules recognised selectively transported through nuclear pore into or out of nucleus
> eg proteins needed for nutrients function move from cytosol in to nucleus
> newly formed RNA molecules move from nucleus to cytosol in this manner |
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Term
LESSON 6 NUCLEUS AND CYTOPLASM
NUCLEUS |
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Definition
- inside nucleus > spherical bodies called NUCLEOLI (singular) functions in producing Ribosomes
- each nucleus is a cluster of protein, DNA and RNA and is not enclosed by a membrane
- nucleoli are the sites of synthesis of rRNA and assembly of rRNA and proteins into the ribosomal units
- nucleoli disperse and siappear during cell division and reorganise once new cells are formed
- within nucleus > most hereditary units called 'genes' which control cellular structure and direct cellular activities
- genes are arranged along chromosomes
- human somatic (body) cell have 46 chromosomes, 23 inherited from each parent
- each chromosome us a long molecule of DNA
>coiled together with several proteins > this complex of DNA, proteins and some RNA, is called CHROMATIN. Total genetic information in cell or organism = GENOME |
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Term
LESSON 6 - LECTURE - NUCLEUS AND CYTOPLASM
MEDICAL SCIENCE WITH DR MARTIN STONE |
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Definition
ORGANELLES
at 42:45 identify organelles in image.
FLAGELLUM; CILIA; CENTROSOME; NUCLEUS; ROUGH ER; SMOOTH ER; SECTRETORY; VESICLE; LYSOSOME; GOLGI COMPEX; MITOCHONDRIAN; CYTOSKELETON; RIBOSOMES
Flagellum - moves substances across the surface of a cell |
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Term
| LESSON 7 - EPITHILIAL TISSUE |
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Definition
- Epithelial; EPI Centre
- Apical surface; layer, outer layer, free/exposed
- Basal Surface; basement/bottom surface
- Avascular; no blood supply
- Does have nerve supply |
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Term
LESSON 7 - EPITHILIAL TISSUE
COVERING + LINING EPITHELIUM |
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Definition
Number of layers
> simple; 1 thin layer
> stratified; more than one layer
> pseudo-stratified; looks more than one layer, but only single
Shape of cells
> squamous; flat
> cuboidal; cube shape
> columnar; column shape
> transitional; change shape/can change
Non-Keratinised; doesn't entertain Keratin
Keratinised; contains keratin; makes cells/tissue stronger |
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Term
| LESSON 7 - EPITHILIAL TISSUE |
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Definition
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
COMPARISON BETWEEN EPITHELILAL + CONNECTIVE TISSUE |
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Definition
Epithelial tissue:
- many cells closely packed together; little matrix between them
- Avascular; free surface
Connective Tissue
- Cells embedded in a matrix and widely spaced apart
- Most CT has rich blood supply
- Adjacent to other tissues |
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Term
| LESSON 8 - CONNECTIVE + OTHER TISSUES |
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Definition
- extracellular matrix has two components; ground substance and protein fibres
Protein fibres
> collagen; tough and strong
> elastin fibres; provide elasticity to allow tissue to spring back into shape
> Reticular fibres; thin and delicate, often found in organs |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Summary |
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Definition
Connective tissue consists of:
Cells
Matrix is made of:
Ground substance
Water
Polysaccharides specifically called glycosaminoglycans (GAGs)
Hyaluronic acid
Chondroitin sulphate
Dermatan sulphate
Keratan sulphate
Proteoglycans
Protein fibres
Collagen Fibres
Elastic fibres
Reticular fibres |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CLASSIFICATION OF CONNECTIVE TISSUE - LIST OF CLASSIFIED> |
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Definition
Embryonic connective tissue
Mesenchyme
Mucous connective tissue
Mature connective tissue
Loose connective tissue
aereolar connective tissue
Adipose tissue
Reticuregular connective tissue
Dense irregular connective tissue
Elastic connective tissue
Cartilage
Hyaline
Fibrocartilage
Elastic cartilage
Bone tissue
Liquid connective tissue
Blood tissue
Lymph
- the second major class of connective tissue is found in a newborn |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CONNECTIVE TISSUE |
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Definition
Connective tissue has a variety of functions:
- binds together, strengthens and supports other tissues
- protects and insulates internal organs
- divides/categorises structures such as skeletal muscles
- primary location for stored energy and main source of immune response
General features of connective tissue:
EXTRACELLULAR MATRIX + CELLS |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CONNECTIVE TISSUE
> EXTRACELLULAR MATRIX + CELLS |
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Definition
Extracellular consists of
> proteins
> ground substance; material between cells and fibres
Extracelluar matrix of bone, by contrast, is hard and flexible |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CONNECTIVE TISSUE CELLS |
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Definition
- Embryonic cells > mesenchymal cells > give rise to the cells of connective tissue
- each major type of connective tissue contains an immature type of cell with names ending in "blast" which means to "bud or spout" |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CONNECTIVE TISSUE CELLS |
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Definition
Fibroblasts > large flat cells with branching processes
Macrophages > develop from monocytes, a type of white blood cell, short branching projections, engulf bacteria and cellular debris by phagocytosis
Plasma cells> are small cells that develop from a type of white blood cell called B lymphocyte
Mast cells> abundant alongside the blood vessels that supply connective tissue, provide histamine as an inflammatory response, can bind to/ingest/kill bacteria
Adipocytes? also called fat cells, are connective tissues that store fats found deep around organs such as heart and kidneys
Leukocytes (white blood cells)> are not found in significant numbers in normal connective tissue. In certain conditions they migrate from blood to connective tissue |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CLASSIFICATION OF CONNECTIVE TISSUE |
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Definition
AEREOLA - widely distributed tissue, "package of the body" consisting of fibres (collagen, elastic, reticular). Functions are strength, elasticity, support.
ADIPOSE TISSUE - cells derived from fibroblasts (called adipocytes) specialised for storage of fats. Located wherever aereola is. Function is reduction of heat loss in skin, serves as energy reserve.
RETICULAR - fine interlacing network of reticular fibres. Location Stroma (supporting framework) liver, spleen, lymphnodes etc.Function - forms stroma of organs, filters and removes worn-out blood cells, binds smooth muscle tissue. |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CLASSIFICATION OF CONNECTIVE TISSUE |
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Definition
DENSE REGULAR - forms shiny extracellular matrix; mainly collagen fibres REGULARLY arranged in bundles with fibroblasts in rows between them. Function - forms tendons, most ligaments, aponeuroses (sheetlike tendons that attach muscle or muscle to bone).
DENSE IRREGULAR - made up of collagen fibres and is used IRREGULARLY arranged with a few fibroblasts. Location; occuring in sheets found in tissues beneath skin, around muscles and other organs, region of dermis of skin, fibrous pericardium of heart, periosteum of bone, cartilage, bone capsules, joint capsules, membrane capsules around various organs (liver, kidney, testes, lymph nodes ) also heart. Function - provides tensile (pulling) strength in many directions
ELASTIC - predominantly elastic fibres with fibroblasts between them. Location: lung tissue, walls of elastic arteries, trachea, bronchial tubes, true vocal cords, suspensory ligaments of penis, some ligaments between vertebrae. Function - allows stretching of various organs, helps maintain blood flow
CARTILAGE (mature connective tissue) - consists of a dense network of collagen fibres and elastic fibres embedded in a chondroitin sulphate, a gel-like component of the ground substance. Cartilage heals poorly because it has no blood supply. Reason is because of the antiangiogenesis factor (meaning; against vessel production).
Cells of the cartilage are called CHRONDRYTES.
Cartilage resists tension/stretching, compression and pushing in opposite directions. Because of this property, antiangiogenesis factor is being studied as a possible cancer treatment. |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CLASSIFICATION OF CONNECTIVE TISSUE |
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Definition
There are three types of cartilage: hyaline cartilage, fibrocartilage, and elastic cartilage
The cells of mature cartilage, called chondrocytes (KON-drō-sīts; chondro- = cartilage), occur singly or in groups within spaces called lacunae (la-KOO-nē = little lakes; singular is lacuna, pronounced la-KOO-na) in the extracellular matrix. A covering of dense irregular connective tissue called the perichondrium (per′-i-KON-drē-um; peri- = around) surrounds the surface of most cartilage and contains blood vessels and nerves and is the source of new cartilage cells. Since cartilage has no blood supply, it heals poorly following an injury. |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CLASSIFICATION OF CONNECTIVE TISSUE |
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Definition
TYPES OF CARTILAGE:
- Hyaline
> contains resilient gel as ground substance
> location: most abundant cartilage in body; found at end of long bones, anterior ends of ribs, nose, parts of larynx, trachea, bronchi, bronchial tubes, embryonic and foetal skeleton.
>Function: Provides smooth surfaces for movement at joints, flexibility, and support; weakest type of cartilage and can be fractured.
FIBROCARTILAGE
>
Fibrocartilage has chondrocytes among clearly visible thick bundles of collagen fibres within extracellular matrix; lacks perichondrium
> Location:
Fibrocartilage has chondrocytes among clearly visible thick bundles of collagen fibres within extracellular matrix; lacks perichondrium
> function:
Support and joining structures together. Strength and rigidity make it the strongest type of cartilage. |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CLASSIFICATION OF CONNECTIVE TISSUE |
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Definition
TYPES OF CARTILAGE -
ELASTIC CARTILAGE
> Elastic cartilage has chondrocytes in threadlike network of elastic fibres within extracellular matrix; perichondrium present.
> Location: Lid on top of larynx (epiglottis), part of external ear (auricle), auditory (eustachian) tubes
> Function:
Provides strength and elasticity; maintains shape of certain structures.
Cartilage, joints, and bones make up the skeletal system.
BONE TISSUE (mature connective tissue)
> Compact bone tissue consists of osteons
> spongy bone tissue consisting of coloumns
> thin coloumns called trabeculae; filled with red bone marrow |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CLASSIFICATION OF CONNECTIVE TISSUE |
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Definition
LIQUID CONNECTIVE TISSUE
> a liquid connective tissue has a liquid as its extracellular matrix
BLOOD TISSUE
>Blood plasma and formed elements: red blood cells (erythrocytes), white blood cells (leukocytes), platelets (thrombocytes). Location: Within blood vessels (arteries, arterioles, capillaries, venules, veins), within chambers of heart. Function: Red blood cells: transport oxygen and some carbon dioxide; white blood cells: carry on phagocytosis and mediate allergic reactions and immune system responses; platelets: essential for blood clotting. |
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Term
LESSON 8 - CONNECTIVE + OTHER TISSUES
Textbook
CLASSIFICATION OF CONNECTIVE TISSUE |
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Definition
LYMPH
> WILL BE STUDIED LATER. |
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Term
| LESSON 9 - THE DIGESTIVE SYSTEM |
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Definition
- gut is the seat of all disease
- digestive system starts from mouth all the way to the anus
- tube is called gastro intestinal tract (GIT) aka alimentary canal
- study of this system is gastro enterology
- most of the GIT layers contain 4 layers of tissue:
> mucosa, submucosa, muscularis, serosa |
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Term
| LESSON 9 - THE DIGESTIVE SYSTEM |
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Definition
DIGESTIVE SYSTEM PROCESSES
> ingestion
> digestion
- mechanical
- chemical
> mixing and propulsion
> secretion
> absorption
> defecation
GIT
> mouth/oral cavity
> pharynx
> oophagous
> stomach
> small intestine (liver gal bladder and pancreas)
> large intestine
> rectum
> anus |
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Term
| LESSON 9 - THE DIGESTIVE SYSTEM |
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Definition
Mouth/oral activity
> secretion of saliva
> mechanical digestion
> chemical digestion
Pharynx
> passage way for air, food and drink
Esophagus
> connects pharynx to stomach
> lower esophageal sphincter needs to open to allow food into the stomach, and close properly to prevent acid from the stomach 'refluxing' back up into the esophagus. |
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Term
| LESSON 9 - THE DIGESTIVE SYSTEM |
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Definition
Stomach
> J-shaped organ located in the epigastric region (solar plexus)
> only a few substances are absorbed here (eg alcohol, aspirin), an organ of digestion rather than absorption
> mechanical and chemical digestion, primarily proteins
> seceretes hydrochloric acid (HCI) and pepsin
> also secretes intrinsic factor necessary for b12 absorption further down the GIT
Small Intestine
> secretion of digestive enzymes (chemical digestion)
> mechanical digestion (segmentation and peristalsis)
> site is most absorbed in the GIT
> divided into duodenum, jejunum and ileum
> 3 features to increase surface area:
- circular folds (pilcae circulare)
- villi
- microvilli |
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Term
| LESSON 9 - THE DIGESTIVE SYSTEM |
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Definition
Liver
> largest internal organ
> production of bile
> metabolism of absorbed nutrients
Pancreas
> inferior and posterior to stomach
> head. body and tail
> endocrine and exocrine function
> secretes pancreatic juice, which is alkaline and contains several digestive enzymes |
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Term
| LESSON 9 - THE DIGESTIVE SYSTEM |
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Definition
Large Intestine
> caecum (with appendix) ascending colon, transverse colon, descending colon, sigmoid colon, rectum, anus
> series of pouches called haustra
> absorption of water, electrolytes, some vitamins
> formation and elimination of feces
- liver > largest internal organ, many functions, production of bile, metabolism of absorbed nutrients |
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Term
LESSON 9 - THE DIGESTIVE SYSTEM
TEXTBOOK
OVERVIEW OF THE DIGESTIVE SYSTEM CHP 24 |
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Definition
> GI TRACT is 5-7 metres long, 7-9 metres after death due to muscle loss
> organs of the gastrointestinal tract include mouth, pharynx, esophagus, stomach, small intestine, large intestine.
> Accessory digestive organs consist of tongue, teeth, slivary glands, liver, gal bladder, pancreas.
> other digestive organs don't come into contact with food ie they produce or store secretions that flow into the GI tract through ducts; the secretions aid the chemical breakdown of food. |
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Term
LESSON 9 - THE DIGESTIVE SYSTEM
TEXTBOOK
OVERVIEW OF THE DIGESTIVE SYSTEM CHP 24 |
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Definition
- Refined foods reduce the variety of microbes and can affect immunity
- they found the interaction between food and gut microbiota were affected by the availability and dependency of nitrogen
- microbes do 3 things; extract energy from foods, contribute to improving nutrient quality of the diet, contributing to defence against pathogens and immune functioning.
- microbes that cooperate with us support immune function, microbes that dont affect the immune system and thats why its beneficial to have a diet that supports microbiota e.g intermittent fasting or low GI diet promotes microbial cooperation
- refined foods may not even reach the larger intestine and are digested early on as they don't require the assistance of microbes. It is important to have a variable diet to increase microbiota. |
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Term
LESSON 9 - THE DIGESTIVE SYSTEM
TEXTBOOK
OVERVIEW OF THE DIGESTIVE SYSTEM CHP 24 |
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Definition
- Two types of organs compose the digestive system; gastrointestinal tract and accessory organs.
- gastrointestinal tract is a continuous cube that starts from mouth to anus through the thoracic and abdominopelvic cavities
Functions of the digestive system:
- ingestion; taking food into the mouth
- secretion; release of water, acid, buffers and enzymes into lumen of GI tract
- mixing and propulsion; churning and movement of food through the GI tract
- digestion: mechanical and chemical breakdown of food
- absorption: passage of digested products from the GI tracts into the blood and lymph
- Defecation: elimination of feces from the GI tract |
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Term
LESSON 9 - THE DIGESTIVE SYSTEM
TEXTBOOK
OVERVIEW OF THE DIGESTIVE SYSTEM CHP 24 |
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Definition
- the GI tract contains food from the time it is eaten until digested and absorbed or eliminated.
- defecation: materials not absorbed by the body ie waste, indigestible foods, bacteria.
- enzymes that are secreted from accessory organs help to breakdown foods chemically with the assistance of contractions from the GI tract
Overall the digestive system has 6 basic practices:
- ingestion
secretion > everyday cells extract 7 litres of water from GI Tract and accessory organs of acid, buffers, enzymes into lumen (interior space of GI tract)
- mixing and propulsion, digestion > cotractions back and forth aid in moving foods down towards the anus; scientific name for it "motility"
- digestion: mechanical and chemical processes breakdown food into small molecules the aided buy the smaller intestine.ie teeth is mechanical, stomach is chemical.
- a few substances in foods can be absorbed without chemical digestion eg vitamins, ions and cholesterol.
- absorption: the entrance of ingestion and secreted fluids, absorbed substances pass through blood and lymph and circulate through cells around the body |
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Term
LESSON 9 - THE DIGESTIVE SYSTEM
TEXTBOOK
PERITONEUM |
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Definition
- largest serous membrane of the body
- lines wall of the abdominal cavity (parietal peritoneum)
- consists of layer of epithelium with underlying supportive layer of connective tissue
- some organs are covered on the posterior abdominal wall and are covered by the peritoneum on their anterior surfaces ie kidneys, ascending/descending colons of the large intestine, duodenum of small intestine, and pancreas, said to be retroperitoneal (retro = behind)
- unlike pericardium and pleurae (which cover heart and lungs) the peritoneum contains large folds that weave between the viscera
- folds bind the organs to one another and to walls of abdominal cavity
- 5 major peritoneal walls; the greater omentum (contains adipose tissue which can expand weight gain/cause beer belly) falciform ligament, lesser omentum, mesentery and mesocolon |
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Term
| START Lesson 10: Organs of the upper GIT |
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Definition
PERITONEUM
The peritoneum (per′-i-tō-NĒ-um; peri- = around) is the largest serous membrane of the body; it consists of a layer of simple squamous epithelium (mesothelium) with an underlying supporting layer of areolar connective tissue. The peritoneum is divided into the parietal peritoneum, which lines the wall of the abdominal cavity, and the visceral peritoneum, which covers some of the organs in the cavity and is their serosa (figure 24.4a). |
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Term
LESSON 10: ORGANS OF THE UPPER GIT
TEXTBOOK
MOUTH |
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Definition
MOUTH/ORAL CAVITY:
> mouth; also referred as oral or buccal cavity
> formed by cheeks, hard and soft palates and tongue
> cheeks covered externally by skin and internally by a mucus membrane which consists of nonkeratinized stratified squamous epithelium
> buccinator muscles and tissue lie between the skin and mucus membrane
> lips also known as labia (fleshy borders)
> lips contain orbicularis oris muscle, covered externally by skin, internally by mucus membrane
> labia frenulum: inner surface of each lip attached to corresponding gum by a midline fold of mucus membrane
> contraction of buccinator muscles and orbicularis oris muscles help keep food between teeth and also assist with speech |
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Term
LESSON 10: ORGANS OF THE UPPER GIT
TEXTBOOK
MOUTH |
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Definition
Oral Vestibule
> the canal / passage way bound externally by cheeks and lips, externally by gums and teeth
> fauces; word for passages
> opening between oral cavity and oropharynx (throat)
Palate
> wall/"septum" that separates the mouth and nasal cavity
> forms roof of mouth
> makes possible to chew and breathe at same time
> hard palate: anterior portion of mouth is formed by maxillae and palatine bones and covered by mucus membrane - forms boney partition between oral and nasal cavities
> soft palate; posterior portion of roof of mouth - arched shaped muscular partition between oropharynx and nasopharynx lined with mucus membrane
> hanging from soft palate is fingerlike muscular structure called Uvula = little grape
> soft palate and uvula draw together to prevent food entering nasal cavity |
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Term
LESSON 10: ORGANS OF THE UPPER GIT
LESSON PAGE |
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Definition
> mouth plays important role in digestion
> can help clients improve digestion by just getting them to take their time when chewing their food
> most obvious role of mouth is mechanical digestion
> the more thoroughly food is chewed, the larger the area for our stomach to chew/breakdown food / for our enzymes to break down chemical bonds
> some chemical digestion occurs in mouth as our salivary glands secrete enzymes
> chewing food slows down the rate at which we eat, getting fuller earlier |
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Term
LESSON 10: ORGANS OF THE UPPER GIT
TEXTBOOK
24.6 PHARYNX |
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Definition
PHARYNX
> when food is swallowed it goes from mouth to pharynx (throat); funnel-shaped tube that goes from nares to esophagus and to the larynx
> composed of skeletal muscle and lined with mucus membrane
> divided into 3 parts; nasopharynx (raspatory function) , oropharynx (respiration and digestion), laryngopharynx (respiration and digestion)
> food passes through oropharynx and laryngopharynx helping food go to esophagus and into stomach
> pharynx is part of respiratory and digestive system |
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Term
LESSON 10: ORGANS OF THE UPPER GIT
TEXTBOOK
OESOPHAGUS |
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Definition
OESOPHAGHUS
> collapsible muscular tube about 25cm long (10inch)
> begins at inferior end of laryngopharynx, passes through inferior aspect of neck, enters mediastinum anterior to the vertebral column
> pierces diaphragm in opening called esophageal hiatus and ends in superior portion of stomach
> protrusion of stomach above diaphragm is called a hernia
> mucosa of the esophagus consists of nonkeratinized stratified squamous epithelium, lamina propria (areola connective tissue)
> near the stomach, the mucosa of the oesophagus also contains mucus glands
> stratified squamous epithelium protects against abrasion when food is being chewed mixed with secretions and swallowed
> upper oesophageal sphincter regulates movement of food from pharynx into oesophagus
> lower oesophageal sphincter regulates food from oesophaghus into the stomach |
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Term
LESSON 10: ORGANS OF THE UPPER GIT
TEXTBOOK
DEGLUTITION |
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Definition
DEGLTITION
> deglutition is movement of food from mouth to achieve swallowing
> facilitated from secretion of saliva and mucus involved in mouth, pharynx and oesophagus
> swallowing occurs in 3 stages; (voluntary stage) bolus/food passed into pharynx), pharyngeal stage (involuntary) pharynx into oesophagus, oesophagual stage (involuntary) oesophagus to stomach
> circular muscles contract, bringing the food down the oesophagus
> PERISTALSIS is the progression of contractions, longitudinal layers of muscular movement that pushes bolus/food onward
> PERSTALSIS is controlled in the oesophaghus by the medulla oblongata. Perstalsis also occurs in other tubular structures of GI tract inc uterer, bile ducts, uterine tubes |
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Term
LESSON 10: ORGANS OF THE UPPER GIT
TEXTBOOK
DEGLUTITION - SWALLOWING |
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Definition
| Mucous secreted by oesophageal glands lubricates the bolus and reduces friction. The passage of solid or semisolid food from the mouth to the stomach takes 4 to 8 seconds; very soft foods and liquids pass through in about 1 second. |
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Term
| LESSON 10 - SUMMARY OF STOMACH |
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Definition
- stomachs main job is digestion, particularly proteins
- not much absorption occurs nor of carbohydrates or fats
- stomach is acid bath where denature of proteins occur
- stomach is made of proteins, but cannot digest itself due to the mucus lining protecting it
- secrets gastric juice to form chemical digestion which helps kill bacteria in food
- stomach contains folds called RUGAE which enable stomach to expand to accomdate a meal
- food is chewed up in the stomach by muscular contractions
- pyloric sphinter regulates food while saucy substance called chyme into the small intestine |
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Term
| LESSON 10 - SUMMARY OF STOMACH |
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Definition
- different types of cells perform in the stomach for different functions; refer back to textbook Histology of Stomach for more info
- PEPSIN; breaks down proteins > INACTIVE "pepsinogen".In the prescence of Hydrochloric Acid (HCI) it becomes its ACTIVE form, Pepsin
- carbohydrates in the stomach pass relatively quickly, while fats stay there for longer, making you feel fuller for longer. |
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Term
| Lesson 11: Organs of the lower GIT |
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Definition
SMALL INTESTINE:
-More digestion/absorption happens
-Large area for absorption created, with circular folds villi and microvilli
-Small intestine begins at pyloric sphincter of stomach, coils into abdominal cavity then into large intestine
-Averages 2.1cm diameter, 3m in length; 6.1m after loss of muscle tone after death
-Small intestine divided into 3 regions; duodenum, jejunum, ileum |
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Term
| Lesson 11: Organs of the lower GIT |
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Definition
-If you were to unfold a SI, it could cover the surface of a tennis court
-First fold is called piclae circulars, microscopic finger-like projections called villi, then lining the villi is microvilli
-Brush border enzymes; microvilli so small they are called brush borders; cells secreting digestive enzymes from villi
-Muscular contractions in the SI is called SEGMENTATION; like squeezing on either end and in the middle; segments.
-Another type of muscular contraction ‘peristalsis’ like a Mexican wave that fizzles out |
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Term
Lesson 11: Organs of the Lower GIT
Small Intestine |
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Definition
-Proteins from food don’t get absorbed and are foreign to the body; not belonging to self; immune system attacks proteins…amino acids are absorbed from the proteins, so the body can make it’s own proteins
-Amino acids and sugars get absorbed into bloodstream
-Fats are absorbed into lymphatic system and dumped into subclavian vein |
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Term
Lesson 11: Organs of the GIT
Large Intestine |
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Definition
LARGE INTESTINE:
-By the time chyme has reached the LI we have extracted what we need from it, the rest is material
- Most of LI is termed the colon and is made up into 3 parts; ascending colon, transverse colon and descending colon
-Last loop before the rectum is the sigmoid colon – common site for bowel cancer
- Colon loses tone with age, exercise helps maintain tone
-Rectum is temporary storage for faeces ready to be expelled |
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Term
Lesson 11: Organs of the GIT
Large Intestine |
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Definition
-Overriding reflex for faeces to be expelled is very unhealthy
-The longer faecal matter is left in the rectum the more toxins are reabsorbed into the body
-Cauceum (with appendix) ascending, transverse, descending, sigmoid, rectum and anus
-Series of pouches called Haustra
- Absorption of water, electrolytes, some vitamins
-Formation and elimination of feces |
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Term
Lesson 12: Accessory organs of digestion, and how the whole system works
LIVER |
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Definition
- heaviest gland of the body 1.4kg approx, inferior to the diaphragm
- gall bladder is 7-10cm in size, sits in a depression posterior to liver
- almost completely covered by visceral peritoneum
- liver is divided into 2 principal lobes ;a large right lobe and a smaller left lobe
- quadrate and caudate lobes belong to left lobe
- falciform ligament helps suspend liver in the abdominal cavity
- falciform ligament; fold of mesentery
- in the free border of falciform ligament is ligamentum teres (round ligament) |
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Term
Lesson 12: Accessory organs of digestion, and how the whole system works
LIVER/GALLBLADDER/PANCREAS |
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Definition
- most of the nutrients we absorb go straight to the liver to be metabolised
- gallbladder stores, concentrates and releases bile
- Pancreas is inferior and popsterior to stomach
* head, body and tail
* endocrine and exocrine function
* secretes pancreatic juice, which is alkaline and contains several digestive enzymes |
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Term
Lesson 12: Accessory organs of digestion, and how the whole system works
LIVER |
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Definition
- blood carrying nutrients that have been absorbed from the small intestine go straight to the liver before they go anywhere else in the body
- liver synthesises bile, bile emulsifies fats for absorption
- gallbladder is a small sack that hangs behind liver; squirts bile into duct that emptys into duodenum |
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Term
Lesson 12: Accessory organs of digestion, and how the whole system works
PANCREAS |
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Definition
- Retroperitoneal gland 12-15cm long and 1cm thick
- lies posterior to the greater curvature of the stomach
- consists of head and body
- EXOCRINE function; secretes pancreatic juice that contains digestive enzymes
- ENDOCRINE function; releases hormones that have the opposite effect in order to create blood sugar homeostasis
- cells of pancreas are grouped into clusters called ancini; most of these cells are exocrine
- pancreatic juice is alkaline; helps to neutralise acidic content coming from stomach into duodenum
- two ducts that empty pancreatic juice into the small intestine; together they form a wider channel called hepatopancreatic ampulla
- pancreatic enzymes; lipase (works with bile which liver produces to break down fat) Protease (breaks down protein in your diet), Amylase (turns starch into sugar, which your body then uses for energy). |
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Term
Lesson 12: Accessory organs of digestion, and how the whole system works
PHASES OF DIGESTION |
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Definition
- Cephalic phase; initial thought or taste of food activates neural centres in the cerebral cortex, hypothalamus and brain stem
- Gastric phase; once food reaches stomach, gastric phase of digestion begins
* consists of both neural and hormonal regulation; NEURAL is mechanical, walls of stomach stretch, pH increases. HORMONAL travels through the body to reach the right organs, G Cells responding to several stimuli, strengthens contraction in esophageal sphincter and promotes gastric emptying, denatures proteins in the stomach |
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Term
Lesson 12: Accessory organs of digestion, and how the whole system works
Ageing and the Digestive System |
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Definition
| - changes in digestion associated with age ie secretory mechanisms, decreased motility of digestive organs, loss of strength and tone in muscular tissue, changes in neurosensory feedback regarding enzyme and hormone release, sensitivity to taste, sores, large intestinal changes such as constipation, hemorrhoids, cancer of the colon |
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