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PHYSIO
Test 1
130
Physiology
Undergraduate 1
09/05/2012

Additional Physiology Flashcards

 


 

Cards

Term
Homeostasis
Definition

 

the maintenance of optimal physiological conditions within the body so that vital functions can be performed without deviations or disturbances.

 

**dynamic (ever-changing and adjusting)

Term

Components of homeostatic feedback loop 

 

Definition

1. Receptor (sensor): monitors a controlled condition

 

2. Integrating center (Control center): usually the brain--determines next action

 

3. Effector: receives directions from the control center, produces a response that changes the condition

Term
Negative Feedback Loop
Definition

 

    • original stimulus reversed
 
    • most feedback systems in the body are negative
 
    • used for conditions that need frequent adjustment
 
  • body temperature, blood sugar levels, blood pressure
Term
Example of Negative Feedback
Definition

Homeostasis of Blood Pressure

Pressure receptors in walls of certain arteries detect an increase in BP

nBlood Pressure = force of blood on walls of vessels

nBrain receives input and signals heart and blood vessels

nHeart rate slows and arterioles dilate (increase in diameter)

nBP returns to normal

 

Term
Positive feedback loop
Definition

noriginal stimulus intensified

nseen during normal childbirth, vomiting, blood clotting

Term
Positive Feedback during Childbirth
Definition

 

nStretch (receptors) in walls of uterus send signals through the nervous system to the hypothalamus (control center), which in turn sends a signal through the nervous system that stimulates pituitary gland

 

nPituitary gland releases oxytocin (messenger) into bloodstream- binds to receptors on smooth muscle of uterus

 

nUterine smooth muscle contracts more forcefully (effector)

 

nMore stretch, more hormone, more contraction etc.

 

nCycle ends with birth of the baby & decrease in stretch

 

Term
Homeostatic Responses
Definition

 

nChemical messengers:

nHormones: chemical secreted into bloodstream

nNeurotransmitters: chemicals secreted by nerve cells

nSend signals to other nerves, muscles, glands

 

Term
Mass vs weight
Definition

Mass: amount of matter in an object

weight: force of gravity acting on matter

**on earth, weight and mass are equal

Term
Chemical elements
Definition

 

112 elements, 92 occur naturally

 

 

26 of naturally occurring elements are in the body

 

Term
Elements of the body
Definition

C-Carbon

O-Oxygen

H-Hydrogen

N-Nitrogen

**Make up 96%

 

Ca-Calcium

P-Phosphorus

K-Potassium

S-Sulfur

Na-Sodium

Cl-Chlorine

Mg-Magnesium

Fe-Iron

**Make up 3.8%

 

Trace elements: Copper, tin, selenium, zinc

Term
Molecule
Definition
More than one atom bound together
Term
Compound:
Definition

 Molecule containing different kinds of atoms

Term
Atomic number
Definition

 number of protons in the nucleus.

Term
Mass number
Definition
sum of its protons and neutrons
Term

 

Unless the shells are full, the electron will be

 

Definition
slightly unstable, even if it is electrically neutral
Term
Cation
Definition
positively charged ion
Term
anion
Definition
negatively charged ion
Term

 

Ionic compounds generally exist as

Definition
solids
Term

 

In the body, materials containing ionic bonds are found mainly in

Definition

 

Teeth, bones, blood

Term
Electrolytes:
Definition

 

nIons in a compound that dissolve in water are called electrolytes

 

nIonic bonds are easily broken by adding water

Term

Electrolytes:

Why does Your Body Need Them?

Definition

Brain, nerves:

1. Powered by electricity

2. Electrochemical energy

 

Muscles (including heart):

1. Calcium (Ca2+) allows muscles to contract

 

Digestive system:

1. Hydrogen (H+) major ion of digestion

 

Regulation of Body Fluids:

1. Blood pressure regulation: (a few examples you need to know)

Sodium (Na+)

Potassium (K+)

Chloride (Cl-)

Phosphate (PO43-)

Hydroxide (OH-)

Calcium (Ca2+)

Magnesium (Mg2+)

Term
Covalent Bonds – strongest bonds
Definition

 

·         Atoms share electrons to form covalent bonds

 

·         Electrons spend most of the time between the two atomic nuclei

 

Term
Polar Covalent Bonds
Definition

·         Unequal sharing of electrons between atoms.

·         In a water molecule, oxygen attracts the hydrogen electrons more strongly

-Oxygen has greater electronegativity as indicated by the negative Greek delta sign.

Term
Water in the body
Definition

Human Body 70% water – medium of chemical reactions

 

Polarity

·         Uneven sharing of electrons

·         Partial negative charge near oxygen atom and partial positive charge near hydrogen atoms

Term

 

Hydrogen Bonds

 

 

Definition

·Formed by the attraction between slightly positive hydrogen atom and a slightly negative atom of another element.

 

·Gives water unique characteristics

 

Term

 

Solvent

 

Definition

Most versatile solvent known – dissolves hydrophilic (polar, water soluble) substances, not hydrophobic (non-polar, oil soluble)

·         Its shape allows each water molecule to interact with neighboring ions/molecules

o   oxygen portion attracts sodium

o   hydrogen portion attracts chloride

o   sodium & chloride separate as ionic bonds are broken

·         Hydration spheres surround each ion and decrease possibility of bonds being reformed

Term
Heat Capacity of Water
Definition

High

·         Can absorb a large amount of heat with only a small increase in its own temperature

o   Large number of hydrogen bonds in water

o   Bonds are broken as heat is absorbed instead of increasing temperature of water

·         Large amount of water in body helps lessen the impact of environmental changes in temperature

·         Evaporation of water from the skin removes large amount of heat

Term
Water Molecules and Solutions: Amphipathic Molecules
Definition

·         Molecules with a hydrophobic region and a hydrophilic region.

o   In water, form clusters with polar regions at the surface, and nonpolar regions in interior of cluster - i.e. Soap

·         Provide specific boundaries for other substances

o   Cell membrane: phospholipids

Term

 

Water as a Lubricant

 

 

Definition

·Major component of lubricating fluids within the body

oMucus in respiratory and digestive systems

oSynovial fluid in joints

oSerous fluids in chest and abdominal cavities

oOrgans slide past one another

 

Term

 

Free Radicals

 

 

Definition

·Atom with an unpaired electron in its outermost shell

·Unstable and highly reactive

·Can become stable by giving up electron, or taking one from another molecule

oAntioxidants attach to electrons

oWithout antioxidants free radicals attach to electrons on body cells, especially nerve tissue.

 

 

 

Term

 

Free Radicals & Your Health

 

 

Definition

 

·Produced in your body by

oUV light

ox-rays

oMajority: during normal metabolic reactions (hydrogen peroxide)

·Linked to many diseases

odiabetes

oAlzheimer’s

oatherosclerosis

o arthritis

 

Term

 

Dissolve acids in water:

 

 

 

Definition
dissociate into H+ and one or more anions
Term

 

Dissolve bases in water:

 

Definition
dissociate into OH- and one or more cations
Term

 

Dissolve salts in water:

 

 

 

Definition
dissociate into anions and cations, none of which are either H+ or OH-
Term

Neutralization reaction:

 

Definition
acid + base à salts + water.
Term

 

pH

 

Definition
represents the concentration of H+ in solution
Term

As pH increases,

 

Definition

 [H+] decreases

A difference of 1.0 in pH means a 10x difference in [H+]

*A solution of pH 7 has 10x the [H+] of a solution with pH 8

Term
Organic compounds
Definition

-Always contain carbon and hydrogen

-usually contain covalent bonds

-usually large, unique molecules with complex functions

 

Term
Types of organic compounds
Definition

 

·         Four major classes of organic compounds (macromolecules or polymers) are

v  Carbohydrates

v  Lipids

v  Proteins

v  Nucleic acids

 

Term
All large molecules (polymers) must be broken down into their...
Definition
monomers (single units) in order to be absorbed from the digestive system into the bloodstream.
Term

 

Carbohydrates

 

 

Definition

·Diverse group of substances formed from – carbon, hydrogen, oxygen

·Examples

vcarbohydrates

vsugars

vstarches

vsaccharides

vcellulose

·Main function is to produce energy

·Hydrophilic

 

Term

 

Three types of carbohydrate molecules

Definition

·         Monosaccharides -one molecule

v  Glucose – most abundant monosaccharide in body

§  Stored in liver as glycogen (a polysaccharide)

·         Disaccharides - two molecules

·         Polysaccharides – many molecules

 

 

 

 

Term

 

Monosaccharides

 

Definition

·simple sugars

·humans can absorb only three types of monosaccharides

·Glucose, fructose, galactose

Term

 

Disaccharides

 

 

Definition

·Formed by combining two monosaccharides: sucrose (fructose + glucose), lactose (galactose + glucose), maltose (glucose + glucose)

 

Term

·         Lactose Intolerance -

Definition
 Inability of the body to produce sufficient lactase enzyme to break down lactose into monosaccharides
Term

 

Polysaccharides

 

Definition

·Contain 10 or 100’s of monosaccharides

·In animals

glycogen –storage in liver

·In plants

starch and cellulose are large carbohydrate molecules used for energy storage

§rice

§potatoes

§grains

Term
Lipids
Definition

Fats Containing Carbon, Hydrogen

(hydrophobic)

Term
Three functional classes of lipids
Definition

1. Storage lipid

2. Regulatory lipid

3. Structural lipid

Term

 

1. Storage lipid

 

 

Definition

Triglycerides- Common body fat: fatty acids + glycerol (energy)

Types of Unsaturated Fatty Acids

§cis - fatty acids

·Angular fatty acid chain: more fluid

§trans - fatty acids

·Straight fatty acid chain: more viscous (like saturated fatty acids)

 

Term

2. Regulatory lipid

 

Definition

Steroids- Act as hormones

Cortisol– anti-inflammatory

Term

3.  Structural lipid

 

Definition
Phospholipids– Form cell membranes
Term

 

Proteins-elements/formation

 

Definition

carbon

hydrogen

oxygen

nitrogen

sulfur

 

**Constructed from combinations of 20 amino acids, held together by peptide bonds

 

Term
Protein functions
Definition

Structural

Hormones

Oxygen transport (hemoglobin)

Cell receptors/channels

Antibodies

Enzymes

Energy

Term
Structure of proteins
Definition

1. Primary: Sequence of amino acids

2. Secondary: chain of amino acid's spatial arrangement IE beta pleated sheet, alpha helix

3. Tertiary: complex 3D shape

4. Quaternary: shape formed by more than one polypeptide chain joining together IE hemoglobin

 

**Shape of protein influences its ability to form bonds and function

Term

 

Protein Denaturation

 

Definition

 

   Unique shape facilitates specific function. If proteins unravel, can’t function

 

   Heat, acid or salts change (denature) three dimensional shape and destroy protein’s ability to function

 

Term

 

Enzymes:

 

 

Definition

 proteins that are catalysts

 

Term
How enzymes work
Definition

 

1. Speed up the rate of chemical reactions

Lower the activation energy for a reaction

2. Are not permanently altered in the reactions

3. Do not change the nature of the reaction

4. Enzymes catalyze reactions by binding the reactants (substrates)

orient them so that less energy is needed to get the reaction going

 

Term

 

Enzymes Catalyze...

 

Definition
 Specific Reactions
Term

Lock and Key Model

Definition

-Enzymes have complex structures

 

-Regions in the structure act as active sites

bind specific substrates

catalyze specific chemical reaction

produce specific products

optimal pH

 

Term

 

Nucleic Acids and function

 

Definition

 

DNA

RNA

 

Function

-Storage of genetic information for protein synthesis

-Energy

 

Term

 

DNA Structure

 

Definition

·         Huge molecules containing

§  carbon

§  hydrogen

§  oxygen

§  nitrogen

§  phosphorus

·         Molecules exist in nucleus of cells

Term

 

DNA Fingerprinting

In identification

Definition

 

1. criminal

2. victim

3. a child’s parents

 

Term
Sources of DNA fingerprinting
Definition

-strand of hair

-drop of semen

-spot of blood

Term
Problems with DNA fingerprinting
Definition

 

1. Only gives probability, not certainty, unlike traditional fingerprinting

2. Can rule out non-paternity, but cannot conclusively prove paternity

Term
ATP
Definition

 

adenosine triphosphate (derivative of nucleic acids)

Energy currency of the body

Releases energy when one phosphate is removed from molecule

 

 

 

Term
Cell theory
Definition

 

nCells are Basic, living, structural and functional unit of the body

 

nCells are the smallest units that perform all vital physiological functions

 

nEach cell maintains homeostasis at the cellular level

 

Term

 

3 Generalized Cell Structures

 

Definition

1. Nucleus

2. Plasma (cell) membrane

3. Cytoplasm

Term
Function of nucleus
Definition

Control center of the cell

 

-46 human DNA molecules or chromosomes

 

-Two sets of 23 chromosomes or diploid

 

Term
Transcription
Definition
the transfer of that information onto amessenger RNA molecule: exported out of nucleus
Term
Genes
Definition

ngenes found on chromosomes represent a total of 30,000 genes in every human

nEach gene gives instructions to build a specific protein

 

Term

 

Plasma Membrane Functions

 

Definition

-Physical isolation

 

-Regulation of exchange with the environment nCell to cell communication

 

-Movement   - microvilli, cilia, flagella

Term
Fluid mosaic model
Definition

Describes structure of plasma membrane

 

1. “Sea of lipids in which proteins float like icebergs”

 

2. Membrane is 50 % lipid and 50 % protein--held together by hydrogen bonds

 

3. Lipid is a barrier to entry or exit of polar substances

 

4. Proteins are “gatekeepers”--regulate traffic through the cell membrane via channels and transporters

 

Term
Lipid bilayer of the cell membrane
Definition

Two back-to-back layers of phospholipid molecules, with cholesterol and glycolipids scattered on and through the double row

 

Term

 

Phospholipids

 

Definition

-Comprises 75% of lipids

-Makes up the Phospholipid bilayer

-Each molecule is amphipathic

 

Term
Phospholipid bilayer
Definition

Two parallel layers of molecules

Term
Amphiapathic
Definition
molecule has both a polar & nonpolar region
Term

 

Function of Cholesterol

 

Definition

Increases stiffness of membrane

(membranes are usually fluid structures)

Term

 

Plasma Membrane Projections

 

Definition

1. Microvilli

2. Cilia

3. Flagella

Term

 

Plasma Membrane Projections

Microvilli

Definition

 

-Fingerlike projections

 

-Greatly increase surface area for absorption (e.g. small intestine)

 

Term

Plasma Membrane Projections

Cilia

Definition

-Shor hair-like structures

Term

Plasma Membrane Projections

Definition

-Long whip-like structures found on mature sperm

*Allows sperm to swim

Term
Types of Membrane Proteins
Definition

1. Integral proteins

2. Peripheral proteins

Term
Integral proteins
Definition
Extend into or across cell membrane
Term
Peripheral proteins
Definition
Attached to either inner or outer surface of cell membrane and are easily removed from it
Term
Channel or Pore proteins
Definition
A passageway to allow specific substance to pass through membranes
Term
Transporter proteins
Definition
Binds a specific substance, changes shape & moves it across the membrane
Term
Receptor proteins
Definition

*Receive chemical messengers (hormones)

 

-Cellular recognition site

-Ligand (chemical signaling molecule) binds to receptor

-Results in reaction in the cell

 

Term
Cell identity marker (I.D. tag)
Definition
nAllows cell to recognize other similar cells
Term
Linker (Membrane Junction)
Definition

 

-Anchor proteins in cell membrane or to other cells

-Allow cell movement

-Cell shape & structure

Term
Enzyme
Definition

-Speeds up reactions

-Substrate binds to enzyme, makes products

Term

 

Membrane Junctions (Linkers)

 

Definition

1. Desmosomes

 

2. Tight junctions

 

3. Gap junctions

Term

Membrane Junctions (Linkers)

 

Desmosomes

Definition

-Allow for stretching

-IE Skin

-Like rivets or spot welds

*cell membranes held together by a thin layer and reinforced by a network of filaments for strength

Term

 

Membrane Junctions (Linkers)

Tight Junctions

Definition

-No extracellular space between cells

-Substances must pass through cells

-Epithelial cells of digestive system

-Allows for control of substances

*membranes tightly bound together by membrane proteins via adhesion belt, preventing passage of materials IE Stomach lining

Term

Membrane Junctions (Linkers)

Gap junctions

Definition

-Protein channels link cytosol region of two adjacent cells

-Limited exchange of small substances between cells

-Heart muscles

*cell membranes bound together by membrane proteins called channel proteins, allowing small materials to pass through gaps

Term
Parts of the cytoplasm
Definition

1. Cytosol

2. Cell organelles

3. Cytoskeleton

Term
Cytosol
Definition

Fluid: Contains enzymes for necessary chemical reactions

  • 75-90% water with other components

1. Large organic molecules suspended by electrical charges

-proteins

-carbohydrates

-lipids

2. Small dissolved organic molecules

-simple sugars

-ions

3. Site of many important chemical reactions

-Production of ATP

-Synthesis of building blocks for macromolecules

 

 

Term
Cell organelles
Definition

Tiny organs, perform funtions to maintain homeostasis

1. Ribosomes

2. Endoplasmic reticulum

3. Golgi apparatus

4. Protein synthesis

5. Lysosomes

6. Peroxisomes

7. Mitochondria 

Term
Ribosomes
Definition

Nucleus tells ribosomes which proteins to make via mRNA

 

1. Packages of ribosomal RNA and protein

-Free ribosomes are loose in cytosol

*synthesize proteins found inside the cell

-Membrane-bound ribosomes

*attached to endoplasmic reticulum

*synthesize proteins needed for plasma membrane or for export

 

Term
Endoplasmic Reticulum
Definition

 

1. Network of membranes forming flattened sacs

2. Rough ER - attached ribosomes

-continuous with nuclear envelope and covered with attached ribosomes

-synthesizes, processes and packages proteins for export

 3.Smooth ER - no attached ribosomes

-synthesizes phospholipids, steroids and fats

-detoxifies harmful substances such as alcohol

-Ca2+ storage

 

*Processes and packages proteins into envelopes called vesicles, then sends to the Golgi apparatus

Term
Golgi Apparatus
Definition

-Processes and packages proteins produced by rough ER

-Processes and packages lipids synthesized by smooth ER

(Post office)

Term

Protein synthesis

-Translation

Definition

nInstructions for making specific proteins is found in genetic coding in the DNA

Translation: The process of reading the mRNA code to form a specific protein

Term
Lysosomes
Definition

-Membranous vesicles

-Filled with digestive enzymes

 

Functions:

-Digest foreign substances

-Autophagy - recycles own organelles

 

*Clean-up crew

Term
Peroxisomes
Definition

-Membranous vesicles

-Contain enzymes that oxidize organic material

 

Function:

-Oxidizes products of normal metabolic breakdown

-Oxidizes toxic substances such as alcohol and formaldehyde

*Contains catalase which decomposes H2O2 ( product of metabolism)

Clean-Up Crew

 

Term
Mitochondria
Definition

Double membrane organelle

 

Function

-Generation of ATP by cellular respiration

-Powerhouse of cell

 

*Look and function like bacteria

*Made from maternally inherited DNA

Term
Cytoskeleton
Definition

Supports and stabilizes cellular structure--made of protein

*Orchestrates cell division

 

Made of:

1. Microfilaments--7nm diameter--Actin

2. Intermediate filaments--10nm diameter--several proteins

3. Microtubule--25nm diameter--Tubulin

Term
Cell reproduction: Mitosis
Definition

Asexual

Cell growth must balance cell death

(G0 phase of mitosis)

1. Prophase

2. Metaphase

3. Anaphase

4. Telophase 

Term

Mitosis

1. Prophase

Definition

-Chromosomes condense and organize

-nuclear membrane and nucleoli disappear

-Spindle attach to centromeres of duplicated chromosomes

Term

Mitosis

2. Metaphase

Definition
-Spindles line up duplicated chromosomes along equator
Term

Mitosis

3. Anaphase

Definition

-Centromere of each duplicated chromosome is separated

-Paired chromatids are pulled apart

Term

Mitosis

4. Telophase

Definition

-Chromosomes uncoil

-Nucleoli appear

-Cytokinesis occurs-->two genetically identical daughter cells are produced

Term
Necrosis
Definition

Pathological cell death

-Death of cells damages adjacent cells

Term
Apoptosis
Definition

Homeostatic cell death

-Process where specific cells die off in a controlled fashion that does not damage adjacent cells

 

Term
Crenate
Definition
cell shrinks
Term
Lyse
Definition
cell bursts
Term
Metabolic pathway
Definition

1. Glycolysis

2. Citric Acid (Krebs) Cycle

3. Electron Transport Chain

Term
1. Glycolysis
Definition

-Splitting of sugar occurs outside of mitochondria

-Process of ten separate reactions in sequence that occur in the cytosol.

- 6-carbon glucose broken down into two 3-carbon molecules

 

C6H12O6  --> 2C3H6O3  + (2 ATP)

 

*Anaerobic-no oxygen used; functions in almost all living organisms

*Muscular pain from over exercise due to waste product of glycolysis (lactic acid)

 

 

Term
2. Citric Acid (Krebs) Cycle
Definition

Aerobic process

 

-Takes over where glycolysis leaves off.

-Takes place in mitochondria

-Each 3-carbon molecule loses one carbon atom:

forms 2-carbon molecule

-Makes 2 more ATP, (one per each 3-carbon molecule)

releases more high-energy electrons, & hydrogen ions

 

Term
3. Electron Transport Chain
Definition

(Oxidative Phosphorylation)

 

Aerobic

 

-In Mitochondria

-High-energy electrons from previous steps (glycolysis and Krebs Cycle) power the process

-Electrons passed down from areas of higher energy to areas of lower energy.

-Movement of electrons powers the active transport of H+ ions out of a mitochondrial membrane.

-When concentration of H+ outside of membrane is greater than inside, H+ rush back in, fueling a pump that produces ATP.

nThis step produces an additional 26-34 molecules of ATP

Term

OVERVIEW -The Final Equation: (Yes, this is important!)

 

Definition

C6H12O6+ 6O2= 6CO2 + 6H2O + (30-38 ATP)

(glucose)

(energy molecules)

Term

How much ATP is produced per glucose molecule

Glycolosis?

Krebs cycle?

Oxidative phosphorylation?

Definition

Glycolosis: 2 ATP

Krebs cycle: 2 ATP

Oxidative phosphorylation: 26-34 ATP

 

TOTAL: 30-38 ATP

Term
Sources of glucose
Definition

1. Food

2. Liver

-Liver stores glycogen

-Enzymes digest glycogen into free glucose

 

Term
Other fuels for aerobic respiration
Definition

(Don't burn cleanly)

 

1. Triglycerides (from adipose tissue)

-Fatty acids enter Krebs cycle

ketones are byproducts

 

2.Protein

-Amino acids enter Krebs cycle

Ammonia and urea (toxic) produced as byproducts

 

Term

 

ATP Transported Out of Mitochondria

 

 

Definition

Used within cell to power cellular functions

 

Term
Tissues
Definition
groups of similar cells which perform similar functions
Term
Types of tissue:
Definition

1. Muscle Tissue

2. Nerve Tissue

3. Epithelial Tissue

4. Connective Tissue

Term
1. Muscle Tissue
Definition

Cells designed for contraction

 

 Three Types:

1. Skeletal Muscle

2. Smooth Muscle

3. Cardiac Muscle

 

Term
2. Nerve Tissue
Definition

-Communication Network

 

Cell types

1. Neurons

-high-speed communication via electrical signals

2.Neuroglia

-support of neurons

Term
3. Epithelial Tissue
Definition

1. Epithelial membranes

-Covers all body surfaces

-Forms barriers, tubes

2. Epithelial glands:

Clusters of epithelial cells that secrete various materials

-Use diffusion, mediated transport, exocytosis to secrete substances

A. Exocrine glands: do not secrete into blood

-Sweat, salivary, glands of digestive system

B. Endocrine glands: secrete into blood

-Hormones, nutrients secreted by liver

 

Term
4. Connective Tissue
Definition

Functions

1. Connection

2. Structure

3. Support

 

General Structure

-Large amounts of extracellular material 

(extracellular matrix)

 

Term
Organs
Definition

 

nMultiple tissue types

 

nOrganized to perform a specific function

 

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