Topic 1 Lifestyle health and risk

Question 1

Explain how can high blood pressure increase the risk of developing a CVD? (3)

Answer 1

-Causes damage to the endothelium of arteries.
-Build up of cholesterol leads to atheroma formation/Inflammatory response.
-Plaque develops, lumen narrows.

Question 2

Explain why a mammal born with a hole between the two ventricles will become easily tired due to lack of energy? (3)

Answer 2

-Oxygenated and deoxygenated blood mix.
-Concentration of oxygen in blood circulating in body reduces.
-Less oxygen available for aerobic respiration.

Question 3

Explain how the diet of a person could affect the development of CVD. (4)

Answer 3

-High salt intake.
-Increases blood pressure.
-Causes damage to endothelium of artery.
-High cholesterol intake.
-High LDL’s can form atheromas.

Question 4

What reduces blood pressure? With an example. (1)

Answer 4

Antihypertensives. Beta blockers.

Question 5

Describe the role of LDLs in the development of atherosclerosis. (3)

Answer 5

-LDL’s increase blood cholesterol.
-Cholesterol causes plaque to form.
-In endothelium of artery.

Question 6

Explain how atherosclerosis can result in damage to heart muscle. (3)

Answer 6

-Narrows lumen of coronary arteries.
-Reducing blood flow to cardiac muscle.
-Reducing aerobic respiration.

Question 7

Explain how a blood clot could form in blood vessel. (4)

Answer 7

-Collagen exposed when wall of blood vessel is damaged.
-Leads to release of thromboplastin.
-Thromboplastin catalyses conversion of prothrombin to thrombin.
-Thrombin catalyses conversion of fibrinogen to fibrin.
-Fibrin forms mesh of fibres and traps red blood cells.

Question 8

Describe how very high blood pressure could result in atherosclerosis. (3)

Answer 8

-High blood pressure damages endothelium of artery.
-Causing inflammatory response.
-Atheroma forms due to cholesterol build up.

Question 9

Explain why platelet inhibitors would reduce the risk of a heart attack. (2)

Answer 9

-Reduce risk of blood clots forming.
-By making platelets less sticky.
-Less likely that blood flow to heart muscle will be blocked.

Question 10

Describe how high blood pressure could be reduced by medication and lifestyle changes. (3)

Answer 10

-Antihypertensive can be taken.
-Reduce salt intake.
-Increase exercise.
-Stop smoking.

Question 11

Explain the effect that a diet high in salt could have on a person’s risk of developing cardiovascular disease. (5)

Answer 11

-High salt intake increases blood pressure.
-Causes damage to endothelium of artery.
-Causes inflammatory response.
-Leading to atheroma formation.
-Arteries narrow increasing risk of blood clots.

Question 12

Devise a procedure to compare the effects of decaffeinated coffee and regular coffee on the heart rate of Daphnia. (4)

Answer 12

-Use a microscope to count the number of daphnia.
-Measure the heart rate of daphnia in plain water, decaffeinated and caffeinated coffee to see heartbeat before and after.
-Ensure they’re measured at same temp for same amount of time.
-Use a T-test to compare results.

Question 13

What happens in atrial systole?

Answer 13

-Atria contracts forcing atrioventricular valves to open.
-Blood flows into ventricles.
-Ventricular diastole occurs during atrial systole.

Question 14

What happens in ventricular systole?

Answer 14

-Ventricle contracts forcing semi-lunar valves to open.
-Blood flows from right ventricle into pulmonary artery.
-And blood flows from left ventricle into aorta.
-Atrial diastole occurs during Ventricular systole.

Question 15

Explain why high levels of sugars in a person’s diet could lead to obesity. (3)

Answer 15

-Energy intake higher than energy output.
-Excess energy converted to fat.
-Leading to weight gain.
-BMI>30 indicates obesity.

Question 16

BMI is used to see if a person is obese, state another method used to indicate obesity? (1)

Answer 16

Hip to waist ratio.

Question 17

Explain how the structure of glycogen allows it to be an energy store. (3)

Answer 17

-Glycogen is a polysaccharide.
-It is branched to allow for rapid hydrolysis.
-Contains 1-4 and 1-6 glycosidic bonds.
-Compact so a large amount of glucose can be stored in a small space.
-Insoluble meaning it doesn’t affect osmosis.

Question 18

Why are LDL’s saturated?

Answer 18

-Contain no carbon-carbon double bond.
-Hydrocarbon chain is saturated with hydrogen.
-Form unbranched linear chains.

Question 19

Why are HDL’s unsaturated?

Answer 19

-Contain a carbon-carbon double bond.
-Double bonds create a kink in hydrocarbon chain.

Question 20

Describe the reaction that joins two α-glucose molecules to form a disaccharide. (2)

Answer 20

-A condensation reaction takes place.
-Water is formed.

Question 21

Compare and contrast structure of glycogen and a disaccharide.(4)

Answer 21

-Both contain glycosidic bonds.
-Both contain glucose.
-Glycogen contains 1-4 and 1-6 glycosidic bonds whereas disaccharides contains only one type of glycosidic bonds.
-Glycogen only contains glucose whereas disaccharides can contain glucose and other monosaccharides.

Question 22

Describe how an enzyme can break down polysaccharides. (2)

Answer 22

Enzymes hydrolyse the glycosidic bonds.

Question 23

What are triglycerides made up of?

Answer 23

One molecule of glycerol and three fatty acids joined by ester bonds formed in a condensation reaction.

Question 24

A student stated that loss of heat when sweating is related to the dipole nature of water molecules.

Justify this statement. (3)

Answer 24

-The water has an uneven distribution of charge making it a dipole.
-Water forms hydrogen bonds with other water molecules.
-Requires a lot of thermal energy to break these bonds.
-To allow water to evaporate.

Question 25

Explain how the properties of water make it an ideal transport medium. (3)

Answer 25

-Water is a solvent.
-Water molecules surround polar molecules.
-Water is a liquid so it has the ability to flow.