Diet & Health Flashcards
what is CVD associated with
Atherosclerosis which is the formation of hard plaques in artery lining
Thrombosis blood clot formation
how does diet have a risk of CVD
diet high in saturated fat increases blood cholesterol levels increases atheroma formation and hence thrombosis
high salt increases blood pressure
how does high blood pressure have risk of CVD
increase risk of damage to artery walls increasing atheroma formation hence thrombosis
how does smoking have a risk of CVD
carbon monoxide combine w haemoglobin reducing oxygen capacity decreasing respiration in brain cells and heart leading to stroke or heart attack.
what are the medication for CVD
Antihypertensives
Statins
Anticoagulants
Platelet Inhibitors
What are Antihypertensives
lowering blood pressure reducing risk of arterial endothelial damage reducing risk of atheroma and thrombosis
Beta blockers vasodilators and diuretics
what do beta blockers do
prevent increases in heart rate
what do vasodilators do
increase the diameter of the blood vessels / prevent constriction of blood vessels
what do diuretics do
reduce blood volume by decreasing the amount of sodium reabsorbed into the blood by the kidneys, therefore decreasing the volume of water reabsorbed into the blood
What do statins do
lowering blood cholesterol
They block an enzyme in the liver which is needed to make cholesterol
lowers the LDL concentration in the blood therefore reducing the risk of atheroma formation
what do anticoagulants do
reduce blood clotting decreases the likelihood of thrombosis and therefore reduces the risk of blood vessels being blocked by blood clots
How do platelet inhibitors reduce risk of heart attack
reduce blood clotting prevent the clumping together of platelets, so preventing the formation of blood clots hence less likely blood flow to heart muscles will be blocked
what are the risks of antihypertensives
headaches drowsiness and swelling of feet and ankles
risks of statins
takes time to be effective.
must be long term and can cause muscle joint pain and liver damage.
nausea
risks of anticoagulants
excessive bleeding
fainting and swelling of tissues
dizziness
risks of platelet inhibitors
excessive bleeding case liver dysfunction
stomach bleeding
what is energy budget
amount of energy taken in by organism minus amount of energy the organism transfers during life processes
What are monosaccharides
a sugar/ monomers of carbohydrate, they join to make carbohydrate polymers
example of monosaccharide
glucose (hexose sugar) formes ring structure.
alpha (alpha) and beta (beta)
Alpha has the H Above
Beta has the H Below
what is the function of a monosaccharide
store energy within their bonds when broken during respiration energy is released. combine through condensation reactions to form larger carbohydrates.
how does the structure of glucose relate to its function
main energy store for animals and plants
It is soluble so can be transported easily
It has many covalent bonds which store energy
how can you make monosaccharides more suitable for storage
bonded together to form disaccharides and ploysaccharides
how are disaccharides and polysaccharides formed
when two hydroxyl (OH) groups on different monosaccharides interact to form a strong covalent bond called a glycosidic bond
what does every glycosidic bond result in
one water molecule being released, thus glycosidic bonds are formed by a condensation reaction
what happens when two molecules of glucose join
form maltose 1,4 glycosidic bonds
what happens when glucose join with fructose
to form sucrose 1,2 glycosidic bond
what happens when glucose join with galactose
form lactose 1,4 glycosidic bond
how can you break glycosidic bond
water is added in a hydrolysis reaction
what is a condensation reaction
Two monosaccharides can join together via condensation reactions to form disaccharides. glycosidic bond formed with a molecule of water released
what is the function of disaccharides
provide the body with a quick-release source of energy as disaccharides are made up of two sugar molecules so they’re easily broken down by enzymes
why are disaccharides easily soluble
Due to the presence of a large number of hydroxyl groups, disaccharides are easily soluble in water these hydroxyl groups form hydrogen bonds with the water molecules
explain structure of polysaccharide
repeated chains of many monosaccharides joined by glycosidic bonds in a condensation reaction
what does branched polysaccharide lead to
Being branched increases the rate at which a polysaccharide can be broken down
what does straight and coiled polysaccharide lead to
Being straight makes the molecules suitable for constructing cellular structures e.g. cellulose
Being coiled makes a molecule more compact and suitable for storage
why are starch and glycogen useful as storage polysaccharides
Compact; large quantities can be stored
Insoluble; they will have no osmotic effect, unlike glucose which would increase the solute concentration of a cell and causing water to move in by osmosis
why are starch and glycogen useful as storage polysaccharides
Compact; large quantities can be stored
Insoluble; they will have no osmotic effect, unlike glucose which would increase the solute concentration of a cell and causing water to move in by osmosis
what is starch and how is it made in plants
a storage polysaccharide of plants
Plants make glucose during photosynthesis and the molecules of glucose are joined to make the polysaccharide starch.
what is starch constructed from
amylose: unbranched helix chain with 1,4 glycosidic bonds between a-glucose.
amylopectin: branched molecule containing 1,4 glycosidic bonds between a-glucose molecules and 1,6 glycosidic bond.
easily hydrolysed for use during respiration
what is glycogen
storage polysaccharide of animals and fungi
It is highly branched and not coiled
It contains both 1,4 and 1,6 glycosidic bonds
is compact which means that much can be stored in a small space
which polysaccharide has helix shape
amylose
what is the function of starch
storage polysaccharide of plants; it is stored as granules in plastids
amylose in starch is helical so very compact
amylopectin has branches that provide many glucose molecules that can be easily hydrolysed for respiration or added for storage
function of glycogen
storage polysaccharide of animals/ more branched than amylopectin
which provides more glucose that can be added or removed by hydrolysis this allows quick storage or release of glucose
Glycogen is compact which means that much can be stored in a small space
how are lipids different to carbohydrates
lipids contain a lower proportion of oxygen
describe lipid and name one
Lipids are non-polar and hydrophobic
Triglycerides are a kind of lipid that forms the main component of fats and oils
describe lipid and name on
Lipids are non-polar and hydrophobic
Triglycerides are a kind of lipid that forms the main component of fats and oils
what are the monomers of triglyceride
glycerol and fatty acids
fatty acids contain methyl group known as R group and a carboxyl group RCOOH
how can fatty acid vary
Length of the hydrocarbon chain (R group)
The fatty acid chain (R group) may be saturated (mainly in animal fat) or unsaturated (mainly vegetable oils
what do saturated fatty acids contain
no carbon-carbon double bonds they form unbranched, linear chains
what do lipids make up
Triglycerides are fats and oils
Fatty acid and glycerol molecules are the components that make up triglycerides
how does an ester bond form
when a hydroxyl (-OH) group from glycerol bonds with the carboxyl (-COOH) group of the fatty acid
The formation of an ester bond is a condensation reaction
For each ester bond formed a water molecule is released
Three fatty acids join to one glycerol molecule to form a triglyceride
Therefore for one triglyceride to form, three water molecules are released
what is cholesterol a type of
lipid produced in the body
Cholesterol is transported around the body as lipoproteins
what does HDL contain and do
unsaturated fat, cholesterol, and protein
These moloecules transport cholesterol from body tissues to the liver to be recycled or excreted; they are responsible for reducing blood cholesterol levels when it is too high
HDLs are also thought to contribute to the removal of cholesterol from the fatty plaques that form during atherosclerosis
What do LDL contain and do
LDLs contain saturated fat, cholesterol, and protein
The role of LDL is to move cholesterol from the liver into the bloodstream where it remains until it is required by the cells they increase blood cholesterol levels when it is too low
LDLs bind to receptors on cell surface membranes, enabling them to be taken up by the cells that need them and removing cholesterol from the blood
what do high levels of LDL’s lead to
blockage of these membrane receptors, causing blood cholesterol to rise
Cholesterol contributes to the formation of plaques in the arteries
how is vitamin c detected
titrating it against a solution of an oxidising agent called DCPIP
DCPIP is a blue dye that turns colourless in the presence of vitamin C
method vitamin c detect
Make up a series. e.g. six, of known vitamin C concentrations
Use a measuring cylinder to measure out 1 cm3 of DCPIP solution into a test tube
Add one of the vitamin C solutions, drop by drop, to the DCPIP solution using a graduated pipette or burette
Shake the tube for a set period of time using a stop watch
results of vitamin c experiment
The volume of vitamin C solution required to decolourise DCPIP should decrease as the concentration of the vitamin C solution increases
why does high blood pressure increase risk of cardiovascular disease
high blood pressure causes damage to the endothelium ofthe arteries (1)
* inflammatory response / build-up of cholesterol leads tothe formation of an atheroma (1)
plaque develops and narrows the lumen
describe how diagram would be different if one fatty acid was unsaturated
double bond between carbon atoms and a kink in the fatty acid chain
how does structure of amylopectin and glycogen make suitable for storage
branched therefore can be rapidly hydrolysed (to release glucose)
(1)
ALLOW be brok ignore €
ALLOW space’
• compact so more (energy / glucose) can be stored
(1)
ALLOW
not affect w
• insoluble therefore does not affect osmosis
how does the structure of glycogen allow it to be a energy store
- polymer of glucose
- to provide glucose for respiration
- {branched / contains 1,6-glycosidic bonds / has many terminal ends} for rapid hydrolysis
- compact to allow large amount (of glucose / energy) to be stored in a small space / insoluble therefore no osmotic effect on cells
method to measure how the concentration of vitamin C changes during courses of a feed
5 samples of breast milk tested from different points of feed
titrate the DCPIP with milk samples. volume of breast milk taken to decolourise the DCPIP
make sure volume of DCPIP is controlled. Time taken for it to go from blue to colourless
use calibration curve to determine vitamin c concentration in each breast milk sample
repeat for concordinant results
compare structure of disaccharide and glycogen
disaccharide formed from only one type of glycosidic bond but glycogen contain 1-4 and 1-6
glycogen is made from only glucose but disaccharide made from other monosaccharides
both contain Hydrogen, Oxygen, Carbon and both contain glycosidic bonds and glucose
how does glucose move into cell by facilitated diffusion
via carrier proteins in the cell surface membrane that change shape once glucose binds to it moving it across the membrane from high concentration to low concentrations
how is trehalose formed
two molecules of a-glucose form 1-1 glycosidic bond
medical advice that could reduce risk of developing CVD for someone who doesn’t have high blood pressure
reduce energy intake / increase activity / follow calorie controlled diet / eq;
2. idea of change in balance of energy budget
lower {weight / BMI / obesity level / eq} / reduce risk of {atherosclerosis / diabetes / eq};
statins / sterols / reduce { cholesterol / saturated fats / eq} in diet / eq;
5. reduce blood cholesterol levels;
6. idea of reducing risk of atherosclerosis /eg;
eat more fruit / vegetable / vitamins / moderate alcohol intake / eq;
8. reference to antioxidants;
9. they protect against free radical damage / reduce damage to cells / eq
anticoagulants / platelet inhibitory drugs / warfarin / aspirin / eq;
11. prevent blood clot formation / eq;
12.reduces risk of blocking artery / eq;
explain why the changes in pressure that occur in the left atrium and left ventricle are different
{pressure changes / maximum pressures} are smaller in the atrium than the ventricle / eq;
2. the atrium has less (cardiac) muscle than the ventricle;
3. the atrium does not have to push the blood as far as the ventricle has to / eq;
4. the increase in pressure happens in the atrium before the ventricle / eq;
5. idea that atrial systole has to happen before ventricular systole in order for the ventricle to fill with blood;
6. idea that increase in atrial pressure causes increase in {pressure / volume
} in ventricles;
7. appropriate reference to effect of atrioventricular valve (AV) (on pressure);
explain how SAN ensures that oxygenated blood enters the Aorta
idea that initiates electrical activity over atria;
causes atria to contract / eq;
{forcing / eq} the (oxygenated) blood into the left ventricle / eq;
electrical activity from SAN {received by AVN / travels through {bundle of His / Purkyne fibres / eq
}};
causing left ventricle to contract (forcing blood into aorta) / eq;
How can anticoagulants reduce effects of CVD
prevent the formation of a {blood clot / thrombus / embolism / eq} / eq;
. idea that it reduces ‘stickiness’ of platelets;
. idea that clotting factors {not synthesised / inhibited / eq};
idea that (risk of) blood vessels becoming blocked is reduced
what is a biological catalyst
a protein made in organisms / cells that reduces activation energy
why may prefer PGD over amniocentesis
fewer ethical issues (with PGD) as the embryo has not been implanted / amniocentesis carried out at a later stage (1)
- no risk of miscarriage from PGD / risk of miscarriage from amniocentesis (1)
One cause of coronary heart disease is atherosclerosis. Describe how
atherosclerosis develops.
damage to {endothelial cells / epithelial cells
/cells lining artery (wall)} ;
2. reference to inflammatory response ;
3. reference to (accumulation of) white blood
cells in (damaged area) ;
4. {build up / eq} of cholesterol (in damaged
area) ;
5. reference to build up of {calcium salts / fibrous
tissue / fibrin / platelets} ;
6. reference to formation of {atheroma /
plaque} ;
7. reference to {loss of elasticity (of artery) /
narrowing of lumen} / eq ;
8. idea that this process is self–perpetuating
Explain how lowering blood cholesterol levels can reduce the risk of CVD.
(less) cholesterol (in blood) to build up on
artery (wall) / eq ;
2. less likely to develop atherosclerosis / eq ;
- credit correct reference to subsequent
consequence of atherosclerosis e.g.
narrowing of arteries,
