cardiovascular disease content

Question 1

bmi

Answer 1

body mass(kg) / height^2 (m)

Question 2

obese bmi

Answer 2

30-40

Question 3

waist to hip ratio

Answer 3

better measure of obesity than bmi
shows highly significant association with risk of heart attack

Question 4

working out W:H ratio

Answer 4

divide waist circumference by hip circumference
men- avg 0.9
women- avg/ healthy 0.85

Question 5

factors contributing to obesity

Answer 5

high sugar/ fat diet
sedentary lifestyle

Question 6

consequences of obesity

Answer 6

increased risk of CHD, stroke, type II diabetes
greater fat= more strain on heart
raises BP and elevate blood lipid levels

Question 7

LDLS

Answer 7

low density lipoproteins- transport cholesterol to body cells (‘bad’)
triglycerides (from fats in diet) combine with cholesterol an protein to form LDL
circulate in bloodstream and bind to receptor sites on cell membranes before being taken up by cell

Question 8

role of cholesterol in cells

Answer 8

involved in synthesis and maintenance of cell membranes (LDL)

Question 9

effect of high LDL

Answer 9

excess LDL overload membrane receptors resulting in high blood cholesterol levels
excess LDL cholesterol may be deposited in artery walls- forming atheromas

Question 10

HDLs

Answer 10

high density lipoproteins (‘good’)
higher percentage of proteins than cholesterol compared to LDLs
made when triglycerides (from fats in diet) combine with cholesterol and protein

Question 11

benefit of HDL

Answer 11

transport cholesterol from body tissues to liver where it is broken down
lowers blood cholesterol levels and helps remove fatty plaques of atheromas

Question 12

saturated fat effect

Answer 12

increases LDL cholesterol greatly and HDL cholesterol a little
may reduce activity of LDL receptors so LDLs are not removed from the blood- further increasing blood cholesterol levels

Question 13

effect of unsaturated fat

Answer 13

if replacing saturated fat in diet:
reduces LDL cholesterol AND HDL cholesterol
increases HDL: LDL ratio- has a protective effect

Question 14

measuring cholesterol levels

Answer 14

difficult + expensive to measure only LDL level
easy to measure total cholesterol level
can use a home testing kit- useful for someone suspected of being at risk of CVD

Question 15

effect of smoking on circulatory system

Answer 15

CO binds to haemoglobin instead of oxygen
- reduces amount of oxygen supplied to cells
- increases heart rate to increase oxygen to cell
nicotine in smoke stimulates production of adrenaline
- causes increase in HR and constriction of arteries and arterioles
- raises blood pressure
chemicals in smoke can cause damage to lining of arteries- triggering atherosclerosis
linked to decrease of HDL cholesterol level

Question 16

effect of in/activity

Answer 16

inactivity is a risk factor for heart disease
moderate exercise prevents high blood pressure
exercise raises HDL cholesterol without raising LDL levels
reduces chance of developing type II diabetes and helps manage/ control T2D if it is already present
a physically active person is more likely to survive a heart attack/ stroke compared to an inactive person

Question 17

heredity

Answer 17

some diseases (eg. simple genetic disorders) have a single risk factor: inheriting a defective allele
different mutations of the defective gene may affect how severe the disease/ symptoms are

Question 18

susceptibility

Answer 18

some diseases result from interactions of several genes
some genes may not directly cause disease but increase chance of developing it
- genes increase the individual’s susceptibility to the disease

Question 19

familial hypercholesterolaemia (FH)

Answer 19

mutations in LDLR gene cause LDL receptors to not form/ or have a shape that makes them less efficient
this decreases/ stops removal of LDL from the blood
results in high LDL levels an early onset CHD

Question 20

apolipoprotein gene cluster

Answer 20

associated with cardiovascular disease and other conditions such as Alzheimer’s
some alleles are linked to a higher risk whereas others may reduce the risk

Question 21

apolipoproteins

Answer 21

protein component of lipoproteins
mostly formed in liver and intestines
roles in stablising structure of lipoproteins and recognising receptors involved in lipoprotein uptake on plasma membrane of cells in body
several types of APO

Question 22

APOA

Answer 22

major protein in HDL
helps in removal of cholesterol to liver for excretion
mutations in apoA gene associated with low HDL levels + reduced removal of cholesterol from the blood
leading to increased risk of CHD

Question 23

APOB

Answer 23

main protein in LDL- transfers cholesterol from blood to cells
mutations in apoB gene associated with higher levels of LDL in blood + higher susceptibility to CVD

Question 24

APOE

Answer 24

major component of HDLs and VLDLs- involved in removal of excess cholesterol from blood to liver
3 common alleles of APOE
APOE4 slows removal of cholesterol from blood- increases risk of CHD

Question 25

APO + CHD risk

Answer 25

many alleles/ mutations make it diffucult to estimate effect future testing of APO levels in blood may be a good indicator for risk of CHD

Question 26

multifactorial diseases

Answer 26

CVD - heredity, physical environment, lifestyle choices, social environment all contribute to risk of development of disease genetic testing for alleles associated with CHD are not very useful because the other factors play a large part in determining risk

Question 27

free radicals in the body

Answer 27

highly reactive can damage many cell components (like enzymes and genetic material) this cellular damage may be linked to the development of some types of cancer, heart disease and premature ageing

Question 28

vitamins + free radicals

Answer 28

provide a hydrogen atom with pairs up with the unpaired electron and stabilises the atom, preventing damage antioxidants

Question 29

salt

Answer 29

high salt diet causes the kidneys to retain water higher fluid levels in the blood result in elevated blood pressure consequently has CVD risks

Question 30

stress

Answer 30

CHD linked to poor stress management adrenaline released in stressful situations - causes arterioles and arteries to constrict- resulting in raised BP stress can lead to overeating, a poor diet and higher alcohol consumption - all potential contributors to CVD

Question 31

alcohol

Answer 31

heavy drinking raises blood pressure, contributes to obesity and can cause irregular heartbeat excess alcohol consumption can result in tissue damage (in liver, brain and heart) - damage increases risk of CVD damage to liver cells impairs ability of liver to remove glucose and lipids from blood

Question 32

function of liver

Answer 32

processing fats, proteins and carbohydrates detoxification- removal and destruction of alcohol from body

Question 33

benefit of alcohol

Answer 33

moderate alcohol consumption correlated with higher HDL cholesterol levels may offer small protective effect against CVD