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BIOL 1, Biology, AQA, AS Level, Britain
COMPLETE
108
Biology
12th Grade
05/19/2014

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Term
For a micro-organism to be considered a pathogen, it must:
Definition
Gain entry to the host, colonise the hosts tissues, resist the hosts defences, and caused damage to the hosts tissues.
Term
A pathogen is:
Definition
An organism that causes disease.
Term
Entrances to the body for disease:
Definition
Gas exchange and digestive systems
Term
Bodies natural defences:
Definition
Mucus layers, enzymes that break down pathogens, stomach acid that does the same
Term
How do pathogens cause disease?
Definition
Damaging body cells, producing toxins
Term
Risk is:
Definition
A measure of the probability that damage to health will occur as a result of a given hazard
Term
Things that increase risk factor for most diseases/health issues:
Definition
Smoking, diet, obesity, lack of exercise, age
Term
Oesophagus:
Definition
Carries food from the mouth to the stomach, has a thick muscular wall
Term
Stomach:
Definition
Muscular sac that produces enzymes, stores and digests food, mostly proteins, has a mucus layer that prevents its own acid digesting it.
Term
Small intestine:
Definition
Long muscular tube, enzymes produced from walls, walls folded into villi and microvilli
Term
Large intestine
Definition
re-absorbs water
Term
Rectum:
Definition
Stores food until it goes to the anus
Term
Salivary glands:
Definition
Produce amylase
Term
Pancreas:
Definition
produces proteases, lipase, and amylase
Term
All digestive enzymes function by:
Definition
Hydrolysis
Term
Monosaccharides have the formula
Definition
(CH2O)n, where n can equal 3,4,5,6 or 7
Term
Benedicts Test
Definition
Add sample to water, grind up if not already liquid, add an equal amount of Benedicts reagent, heat gently, if reducing sugar present it goes red/ orange
Term
Glucose + Glucose
Definition
Maltose
Term
Glucose + Fructose
Definition
Sucrose
Term
Glucose + Galactose
Definition
Lactose
Term
The bonds between monosaccharides are called: ____ and are formed by ___________
Definition
Glycosidic bonds, condensation reaction
Term
Test for non-reducing sugars
Definition
Add food to dilute hydrochloric acid, grind up, boil, then wait for it to cool, slowly add some sodium hydrogencarbonate, check solution is alkaline with pH paper, do Benedicts test
Term
Polysaccarides
Definition
Many monosaccarides joined together
Term
Test for starch
Definition
add iodine, black/blue = positive
Term
These enzymes are produced where, amylase, maltase, sucrase
Definition
Pancreas and salivary glands, epithelium of small intestine, epithelium of small intestine
Term
Lactose Intolerance
Definition
Bodies lose the ability to digest Lactose, so gas is produced when the bacteria in the body digest it instead
Term
Amino acids are joined together to make ______ using a ______
Definition
proteins, peptide bond
Term
Amino acids have ______ functional groups, _____,_____,_____,____
Definition
Four, amino(NH2), carboxyl(COOH), hydrogen(H), R (a variety of different chemicals
Term
Primary structure
Definition
sequence of amino acids
Term
Secondary Structure
Definition
Alpha helix, or beta pleated sheet, hydrogen bonds join them
Term
Tertiary Structure
Definition
Disulfide bonds, ionic bonds and more hydrogen bonds make the protein significant, determines the specific shape and active site
Term
Quaternary structure
Definition
Only in some proteins, can contain non-protein groups such as the iron in haemoglobin
Term
Test for proteins
Definition
Biuret test, add sodium hydroxide, add dilute copper sulfate solution, purple = peptide bonds and therefore protein
Term
Which proteins are structural?
Definition
Fibrous
Term
What to globular proteins do?
Definition
Metabolic functions, such as enzymes
Term
Enzymes lower the __________ of a reaction
Definition
activation energy
Term
Lock and key model:
Definition
Substrate and active site specific and complementary
Term
Induced fit:
Definition
Enzymes active site changes slightly for substrate, allows other, similairly structured molecules in, accepted now
Term
Things that effect enzyme reactions
Definition
temp, substrate concentration, pH
Term
Competitive inhibitors
Definition
Have a similar structure to the substrate, bind to the active site and prevent the substrate doing so
Term
Non-competitive inhibitors
Definition
Bind to the enzyme at a place other than the active site, prevent it binding with the substrate
Term
Magnification =
Definition
Size of image/size of object
Term
Resolution
Definition
Or resolving power, the minimum distance apart two things can be for a microscope to determine that they are separate items.
Term
Cold Fractionation
Definition
Breaking up of cells to see the organelles
Term
Cold, isotonic, buffer solution,
Definition
cold reduces enzyme activity, isotonic prevents organelles bursting or shrinking as a result of osmosis, buffer maintains a constant pH
Term
Homogenation
Definition
cells go in blender, releases organelles
Term
Ultracentrifugation
Definition
Spinning the organelles so the lightest go to the top
Term
Electron microscopes have a higher resolving power because:
Definition
Electrons have a shorter wavelength than light
Term
TEM
Definition
sample must be thin, dead, prepared through staining
Term
SEM
Definition
sample can be thicker, electrons dont penetrate, 3d image, sample must be dead
Term
Nucleus is made up of:
Definition
Buclear envelope, nuclear pores, nucleoplasm, chromatin, nucleolus
Term
Mitochondria:
Definition
Double membrane, Cristae for surface area, Matrix in between, respiration
Term
Rough Endoplasmic Reticulum
Definition
Provides large surface area for protein synthesis, and a transportation pathway for transport of materials
Term
Smooth Endoplasmic Reticulum
Definition
Synthesises, stores and transports lipids and carbohydrates
Term
Golgi Apparatus
Definition
Add carbohydrates to proteins to form glycoproteins, produce secretory enzymes, secrete carbohydrates, transport, modify and store lipids, and forms lysosomes
Term
Lysosomes
Definition
Break down cells when they die, digest pathogens in phagocytosis, digest worn out organelles, release enzymes to outside of cell to destroy things outside it
Term
Ribosomes
Definition
Found mainly in the rough endoplasmic reticulum, protein synthesis
Term
Cell membrane
Definition
Phospholipid bilayer with proteins embedded, and intrinsic proteins acting as channels for facilitated diffusion
Term
Roles of lipids other than phospholipid bilayer
Definition
Energy source, waterproofing, insulation, protection
Term
Test for lipids
Definition
Emulsion test, Add 2cm3 of sample to 5cm3 of ethanol, shake it, add water, shake, cloudy = positive
Term
Cell surface membrane
Definition
Fluid-Mosaic theory
Term
Rate of diffusion is proportional to
Definition
(surface area x difference in concentration)
_____________________________________
length of diffusion pathway
Term
Osmosis is
Definition
the passage of water from a region of high water potential to an area of low water potential through a partially permeable membrane
Term
water enters plant cell
Definition
Turgid
Term
water leaves plant cell
Definition
Plasmolysed
Term
Water enters animal cell
Definition
lysis
Term
Active transport is
Definition
the movement of molecules or ions into or out of a cell from a region of low concentration to an area of high concentration using energy and carrier molecules
Term
Villi and microvilli
Definition
increase surface area for diffusion, thin to reduce diffusion pathway, well supplied with blood vessels, can move to maintain a concentration gradient
Term
Prokaryotic cells
Definition
No nucleus, nucleolus, membrane bound organelles, chlorplasts or endoplasmic reticulum, ribsomes are smaller, circular strands of DNA, peptidoglycan cell wall
Term
Eukaryotic cells
Definition
Nucleolus, nucleolus, chromosomes, golgi apparatus and endoplasmic reticulum, membrane bound organelles, chloroplasts present in plants and algae, cell wall made of chitin or cellulose
Term
Cholera
Definition
If the cholera bacteria survive to the small intestine, they bury themself in the wall, then produce a toxic protein that causes the ion channels of the cell surface membranes to open. This causes chloride ions to flood the small intestine, lowering the water potential and therefore causing water to move in
Term
Cholera is treated with _________ which contain
Definition
Oral Rehydration Solutions, boiled water, sodium, glucose, potassium and other electrolytes
Term
Trachea
Definition
flexible airway that is supported by rings of cartilage, contains mucus and cilia
Term
Bronchi
Definition
Two divisions of the trachea that lead into the lungs, produce Mucus
Term
Bronchioles
Definition
Branching subdivisions of the bronchi
Term
Alveoli
Definition
Minute air sacs surrounded by cappileries , containing elastin and collagen
Term
internal intercostal muscles
Definition
contraction leads to expiration
Term
external intercostal muscles
Definition
contraction leads to inspiration
Term
Pulmonary ventilation =
Definition
tidal volume x ventilation rate
Term
Features of exchange surfaces
Definition
Large SA to VOL ration, very thin, partially permeable, movement of internal and external medium
Term
Tuberculosis
Definition
droplet transmission, grow and divide in upper regions of lungs, generally destroyed by bacteria, this is the primary infection. Years later it can return, and this time it destroys the tissues in the upper lungs, requires up to 9 months of antibiotics
Term
Pulmonary fibrosis
Definition
Scars forming on lung epithelium, increases size of diffusion pathway, reduces elasticity of lungs, causes shortness of breath, coughing, pain and discomfort, weakness and fatigue
Term
Asthma
Definition
Airways inflamed due to immune system response, larger quantities of mucus produced, causes diffluclty in breathing, coughing and a tight feeling in the chest
Term
Emphysema
Definition
Elastin in alveoli damaged, cell walls destroyed, lung surface area reduced, shortness of breath, coughing, cant breath out
Term
Aorta
Definition
connected to left ventricle, oxygenated blood everywhere but lungs
Term
Vena Cava
Definition
connected to right atrium, brings deoxygenated back from the body
Term
Pulmonary artery
Definition
takes deoxygenated blood to the lungs
Term
Pulmonary Vein
Definition
Brings oxygenated blood to the heart
Term
Atrioventricular valves
Definition
prevents backflow to atria
Term
Semi-lunar valves
Definition
prevents backflow to ventricle
Term
Pocket valves
Definition
prevents backflow in veins
Term
Cardiac output =
Definition
heart rate x stroke volume
Term
Sinoatrial and atrioventricular nodes
Definition
Sinoatrial pulses, atria contract, wave reaches atrioventricular, small pause, atrioventricular pulses, travels along bundle of His, and ventricles contract from apex up
Term
Atheroma
Definition
Build up a fatty streaks and white blood cells behind endothelium of blood vessel, narrows the lumen, if it bursts through, thrombosis can occur
Term
Thrombosis
Definition
formation of a blood clot within the vessel, can grow to block the vessel, or become dislodged and block another, if it is a coronary artery it can cause myocardial infarction
Term
Mycocardial infarction
Definition
A heart attack, a coronary artery gets blocked and the oxygen stops being delivered to the heart
Term
Non specific defence mechanisms
Definition
Barriers and phagocytosis, attack all pathogens the same way
Term
Specific defence mechanisms
Definition
Less rapid than non-specific, but provide long-lasting immunity, T lymphocytes and B lymphocytes
Term
How lymphocytes recognise their own cells
Definition
In the fetus, lymphocytes are colliding with their own cells only, so the lymphocytes that have receptors that fit with the bodies own cells are killed or suppressed, and the only ones remaining fit foreign material
Term
Barriers to the body
Definition
Skin, mucus, hydrochloric acid in stomach
Term
Phagocytosis
Definition
Phagocyte attracted to non self material, engulf pathogen, form a vacoule around it, release lysosomes into vacoule, lysosomes break down bacteria, phagocyte absorbs products of digestion
Term
T lymphocytes mature in _____
B lymphocytes mature in _____
Definition
Bone Marrow
Thymus Gland
Term
T lymphocytes work by
Definition
First, phagocytes place antigens of digested pathogens on their surface, then receptors on t lymphocytes fit exactly onto these. This causes other T cells to divide by mitosis, some of these cloned cells become memory cells, others stimulate B cells to divide and phagocytes to attack, and kill infected cells by breaking holes in their cell membranes
Term
B lymphocytes:
Definition
Produce antibodies
Term
Monoclonal antibodies are produced by
Definition
cloning one B cell
Term
Vaccination
Definition
Dead or weakened pathogen is purposely injected into patient so they gain long lasting immunity
Term
Herd immunity
Definition
The majority of the people are immune, so the disease cannot find a pathway to those who arent
Term
Passive immunity
Definition
introduction of antibodies from outside source
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