article Flashcards
(47 cards)
1
Q
what is atherosclerosis
A
is a progressive disease in which plaques (consisting of deposits of cholesterol and other lipids) build up in the walls of arteries
2
Q
what does a tumor mean
A
a group of abnormal cells that form lumps or growths
3
Q
state two factors other than old age,that increase the risk of cvd
A
- obesity
- high blood pressure
- high blood cholesterol
- being male
- lack of exercise
- smoking
- genetics
- high alcohol consumption
- high salt diet
- high saturated fat intake
- stress
- diabetes
4
Q
state levels of organisation
A
cell,tissue,organ,organ system,organism
5
Q
why is coronary heart disease ,more common with old age?
A
- decrease in elasticity of the artery wall
- thus decrease in the ability to respond to changes in pressure
- therefore increase in the resistance to the pumping action of the heart thereby increases the work needed to drive the blood to the various organs of the body
- accumulation of cholesterol,thus increased risk of atherosclerosis
6
Q
explain how the heart rate of a person is controlled as the level of exercise increases during this test (treadmill)
A
- increase in respiration rate in muscle cells
- more co2 in blood (reduced blood ph)
- more lactic acid in blood
- chemoreceptors in medulla stimulated
- ref to cardiovascular control centre in medulla
- ref to autonomic nervous system. sympathetic nerve
- more impulses from medulla to SAN
- more noradrenaline/norepinephrine released onto SAN
- SAN (excitation) rate increased
- causing an icreased heart rate
- comment on other mechanism eg. presence of adrenaline, stretch receptor role
7
Q
why is cancer more common with old age?
A
- accumulation of mutations over years
- accumulations of mutations due to exposure of mutagens over the year
- lose expression of genes (deactivation) important in the cell cycle regulation (due to epigenetic changes -environment)
8
Q
state two categories of genes that when mutated they lead to cancer
A
- oncogenes
- tumour suppressor genes
9
Q
state the name of a tumour suppressor gene , involved in apoptosis, that is commonly deleted in cancer cells
A
p53
10
Q
what happens to the cell cycle if both copies of the tumour suppressor gene are mutated ?
A
- loss of control
- the cell continues through the cycle
11
Q
name one envrionmental factor , other than uv light, that can cause a cell to become cancerous
A
carcinogens/cigarettes/tobacco - ionising radiation/ xrays
12
Q
suggest how the cell cycle will be affected in cells that have become cancerous
A
- shorter growth or G phase/ shorter interphase
- shorter/faster cycle
- cells divide uncontrollably
- cells do not become specialised
13
Q
what is diabetes type 2
A
-the body cannot control /maintain glucose levels
-blood glucose levels are higher than normal
-due to insulin resistance
/ insulin does not work properly
14
Q
difference between lifespan and life expectancy
A
- life span is the maximum time a person can live
- whereas life expectancy is the average time a person will live, based on factors like gender and birth year
- life expectancy is an average.it can be lowered due to infant mortality
15
Q
in 1700 the life expectancy was 30, now it is 77. what is the percantage increase?
A
157%
16
Q
why was life expectancy increased?what has changed?
A
- decline in infants deaths
- better medications
- better health system
- clean water
- warmer housing
- end of child labour
- better management of infectious diseases
17
Q
what does inherent mean?
A
it is intrinsic
18
Q
give one difference between an organ and a tissue
A
- organ has many functions tissue has one/fewer
- organ has several cell types/tissues , tissue has one
19
Q
Suggest one way in which tissues and organs are similar
A
both have cells working together for the same function
20
Q
whats is meant by the term electrocardiogram ECG?
A
- it shows waves/heart rate
- these are waves of electrical activity in the heart
- over a period of time/during a cardiac cycle
21
Q
describe protein synthesis that occurs in the cytoplasm
A
- ribosome attaches to mRNA
- tRNA carries an amino acid
- {anticodon codon interaction / complementary base pairing} between tRNA and mRNA
- peptide bonds between amino acids
- peptide bonds formed by condensation reactions
- tRNA released from {mRNA/ ribosome}
- ribosome moves along mRNA
22
Q
Describe the structure of an enzyme
A
- protein
- 3D/tertiary/globular structure
- ref to named bonds holding structure in place
- between the R groups
- ref to active site
- specificity of active site
23
Q
what are the waste products that could accumulate in a cell
A
- co2
- urea
- nitrogenous waste
24
Q
proteins are made of amino acids. describe how amino acids join together to form the three- dimensional structure of a protein.
A
- peptide bonds joining amino acids
- between amino group of one amino acids and the carboxyl group of the other
- the sequence of amino acids is the primary structure of the protein
- reference to folding (of primary structure) held together by bonds
- disulphide bridges /hydrogen bonds /ionic bonds / van der waals forces
- between R groups
25
state what is meant by the term oxidative phosphorylation
- idea of electrons being passed along the electron transport chain
- idea of losing energy
- used to add a phosphate to adp to make atp
- ref to ATPase
- idea of chemiosmosis
- idea of oxygen as the final acceptor
26
explain why a gene mutation can result in an enzyme that is unable to break down lipids
- change in the dna sequence
- change in amino acids/change in primary structure of protein
- reference to different R groups
- leading to different type and position of bonding
- change in folding (different 3d structure)
- change in shape of the active site
- lipid does not fit in the enzyme's active site
27
name and describe the structures where the polypeptide chain of this enzyme would be synthesised
- ribosomes/rough endoplasmic reticulum
| - descriptive feature eg.ribosomal rna/ rRNA/protein compopent/two sub units,large and small sub unit
28
how can nutrients are taken up by cells. state two ways
- active transport
- facilitated diffusion
- simple diffusion
29
name a repair gene, that when mutated it leads to breast cancer
BRCA1
30
list types of chromosomal damage
- deletion
- insertion
- exchange of regions
- duplication
31
explain how a high concentration of H+ ions is maintained in the intermembrane space
- H+ ions form reduced NAD
- H+ ions pumped into inter membrane space
- energy needed for pump
- movement of e- along ETC
- ETC on inner membrane/ cristae
32
describe the role of the hydrogen ion concentration gradient in making available an accessible supply of energy for biological processes
- H+ ions follow diffusion gradient
- idea that this causes an energy change or makes energy available
- ATP formed
- this occurs in stalked particles
- ATP is energy source for biological processes
33
Describe how you would recognise the golgi apparatus as seen using an electron microscope
- stacks
- cisternae
- smooth membranes/no ribosomes
- curved/flattened
- different sizes (cisternae)
- presence of vesicles
34
explain the roles of RER and the golgi apparatus in a cell
- {protein/polypeptides} produced by ribosome
- ribosomes {held on/attached to } RER
- proteins {stored/transported/within RER}
- proteins folded within RER
- RER produce vesicles
- vesicles fuse with golgi apparatus
- golgi modifies protein
- modification eg.glycoprotein,carbohydrate added
- water removed to concentrate
- golgi produces lysosome/ secretory vesicles
35
lack of 'signals' could lead to muscle atrophy. explain what this means
1. signals are calcium ions Ca2+
2. less Ca2+ binding to troponin so less tropomyosin displaced
3. so less myosin binding sites exposed (on actin) /less myosin binds to actin
4. so there is a lack of muscle use
5. idea that musle atrophy means muscle mass reduction
36
Describe how atherosclerosis develops
1. damage to the endothelial cells of artery/ lining of artery
2. inflammatory response
3. migration of wbc into area
4. build up of cholesterol
5. formation of atheroma/plaque
6. calcium salts/fibrous tissue
7. loss of elasticity of artery//narrowing of lumen
8. self perpetuating process
37
describe the function of ligaments
1. hold / attaches bones together
| 2. still allows movement at the joint
38
suggest why the use of material from tendon will mean that recovery will be quite slow and require careful physiotherapy (torn ligaments)
1. comment on time needed for repair
2. difference in composition of a tendon and a ligament eg.ligament has more elastic fibres ,tendon is inelastic and less flexible
3. need to gradually stretch repaired tissue
39
benefits of keyhole surgery
1. less damage to tissue
2. short time for recovery
3. social benefit (more patients will be treated)
4. economic benefit (cheaper than invasive surgery)
5. less anesthetic needed
40
explain what is meant by the term cruciate ligament
1. in the knee/ behind the knee cap cross shaped ligaments
| 2. connects bone to bone
41
why chose keyhole surgery
smaller incision :-reduces chance of infection
- reduces recovery time
- reduces likelyhood of osteoarthritis
- less scar tissue
- less blood loss
- less pain
42
during old age all tissue are affected including the nervous system. suggest how gene therapy for " moton neurone degeneration diseases "might be carried out
1. ref to restriction enzyme
2. gene inserted into cell/neurones
3. ref to vector
4. liposomes/viruses/plasmid
43
explain why a blood clot in an artery leading to the brain could cause a stroke
1. reduced blood flow
2. less oxygen reaches brain
3. less aerobic respiration
4. less ATP produced
5. brain needs lot of ATP to function
6. lactic acid produced from anaerobic respiration
7. lactic acid inhibits enzymes
44
describe and explain how the lungs of a mammal are adapted for rapid gas exchange
1. alveoli one cell thick
2. walls of capillaries one cell thick
3. alveoli covered with capillaries
4. short diffusion distance
5. diffusion
6. large SA provided by alveoli
7. concentration gradient maintained by ventilation/breathing
8. ref to large numbers of rbc OR oxygen combines with haemoglobin
9. concentration gradient maintained by blood flow
10. fick's law
45
state and explain the effect of exercise on the immune system
one of:
1. low intensity reduces immunity
2. moderate intensity inreases immunity
3. high intensity reduces immunity
46
ficks law:
rate of diffusion= (area of diffusion surface x difference in concentration) ÷ (thickness of surface over which diffusion takes place)
use the information in the formula to explain how the rate of diffusion is affected by aging
1. rate of diffusion is reduced
2. {difference in concentretion gradient/concentration gradient }is reduced
3. smaller surface/area of alveoli
47
explain how the lungs of mammals are adapted for efficient gas exchange
1. large surface area due to many alveoli/many capillaries
2. short diffusion distance due to alveoli/capillaries being one cell thick
3. there is good supply of blood due to many capillaries
