Topic 1 - Lifestyle, Health and Risk

Question 1

What are CVDs?

Answer 1

Cardiovascular Diseases - diseases of the heart and circulation

Question 2

What are Closed Circulatory Systems?

Answer 2

Blood enclosed in tubes. Creates higher blood pressure. Blood travels faster. More efficient.

Question 3

Blood vessels carrying blood from heart

Answer 3

Arteries

Question 4

Blood vessel to lungs

Answer 4

Pulmonary artery

Question 5

Describe a double circulatory system

Answer 5

E.g. Birds and mammals. Right ventricle pumps blood to lungs for gas exchange. Returns to heart. Left ventricle pumps to rest of body.

Question 6

Blood supply to the heart

Answer 6

Coronary arteries

Question 7

Why do animals have a heart and circulation?

Answer 7

To move substances around the body. Overcome limitations of diffusion.

Question 8

What is atherosclerosis?

Answer 8

Disease process leading to CHD and strokes. Fatty deposits can directly block arteries or increase chance of being blocked by a thrombosis.

Question 9

Other useful feature of water in circulation?

Answer 9

High specific heat capacity, so a high amount of energy is required to change the temperature by a small amount, so helps organisms avoid rapid temperature change.

Question 10

Pump to body

Answer 10

Left side

Question 11

Why a double circulatory system?

Answer 11

Gets blood around rest of the body faster, allowing a high metabolic rate as substances needed are delivered more rapidly to cells.

Question 12

Main unique features of veins

Answer 12

Wide lumen, thinner walls, less collagen, elastic fibres, and smooth muscle, vales. Less round shape.

Question 13

Why does blood only flow in one direction?

Answer 13

Valves prevent it flowing back

Question 14

Cardiac Cycle Phase 2

Answer 14

Ventricle systole.Ventricles contract from base upwards pushing blood out through arteries. Pressure of blood against atrioventricular valves closes them and prevents flow back into the atria.

Question 15

What is an Open Circulatory System?

Answer 15

Blood circulates in large open spaces (e.g. In insects). Simple heart pumps blood out into cavities surrounding organs. Substances diffuse between blood and cells. Heart has small valve openings along the length.

Question 16

Result of blocked artery in legs

Answer 16

Tissue death and gangrene

Question 17

What are the main forms of CVDs?

Answer 17

Coronary Heart Disease (CHD) and Stroke

Question 18

Blood vessels carrying blood to heart

Answer 18

Veins

Question 19

Cardiac Cycle Phase 3

Answer 19

Diastole. Atria and ventricles relax, lowering pressure. Blood in arteries (high pressure) drawn back towards ventricles, closing semilunar valves. Coronary arteries fill. Low pressure in atria draws blood back into heart from veins.

Question 20

Blood vessels from lungs

Answer 20

Pulmonary veins

Question 21

One full heartbeat is called…

Answer 21

…a cardiac cycle

Question 22

Why is blood important?

Answer 22

Transport of dissolved substances and cells, regulation of body temperature

Question 23

Main unique features of arteries

Answer 23

Narrow lumen, thicker walls, more collagen, elastic fibres and smooth muscle cells, no valves

Question 24

Cardiac Cycle Phase 1

Answer 24

Atrial Systole. Skeletal and breathing muscles draw blood into heart. Low pressure makes it flow into artia. Pressure builds as they fill opening atrioventricular valves and blood leaks into ventricles. Artia walls contract forcing more blood into ventricles.

Question 25

Capillaries

Answer 25

Very narrow, walls one cell thick. Lie close to all cells allowing rapid diffusion between blood and surrounding cells.

Question 26

Blood vessels from body

Answer 26

Inferior Vena Cava - from lower body Superior Vena Cava - from head and arms

Question 27

Diastole

Answer 27

Heart relaxes, elasticity of artery walls makes them recoil behind the blood, helping to push it forwards. Blood moves along the length as each section stretches and recoils in series.

Question 28

Main blood vessel to body

Answer 28

Aorta

Question 29

What is a stroke?

Answer 29

Restricted blood to brain, damage or death to brain cells.

Question 30

Describe a single circulatory system

Answer 30

E.g in a fish. Blood pumped to gills, oxygen diffuses in, blood flows around rest of the body, eventually returns to gills

Question 31

What are the different types of circulatory system?

Answer 31

Open, Closed, Double

Question 32

Important properties of water

Answer 32

Liquid at room temperature unlike most small molecules. Polar molecule.

Question 33

Pump to lungs

Answer 33

Right side

Question 34

Systole

Answer 34

Heart contracts, blood forced into arteries, walls stretch.

Question 35

What is a heart attack?

Answer 35

Myocardial infarction. Arteries supplying heart are blocked. Cells in heart die.

Question 36

What is mass flow?

Answer 36

Transport of a liquid and all the particles it contains in one direction

Question 37

What is the main cause of death in the UK?

Answer 37

CVDs

Question 38

Solvent properties of water

Answer 38

Many chemicals dissolve easily in water. This allows important reactions to occur in the cytoplasm of cells as chemicals are free to move around and collide. Dissolved substances can also be transported around organisms easily

Question 39

Blood flow in the veins

Answer 39

Assisted by contraction of skeletal muscles during movement of limbs and breathing. Low pressure developed in chest cavity (thorax) when breathing draws blood back into the heart. Backflow prevented by valves. Blood under lower pressure.

Question 40

Similarities of blood vessels

Answer 40

Walls contain collagen - tough fibrous protein, makes then strong and durable Elastic fibres, allows stretch and recoil Smooth muscle cells - constriction and dilation

Question 41

What happens during atherosclerosis?

Answer 41

Something damages the endothelium. Infalmmatory response. White blood cells move into artery wall. These cells accumulate chemicals, particularly cholesterol. Deposit called an atheroma builds up. Calcium salts and fibrous tissue build up. Hard swelling called a plaque. Fibrous tissue build up hardens wall. Plaques narrow artery. Increase in blood pressure.

Question 42

What happens when blood clots?

Answer 42

Platelet plug forms. Blood-collagen contact starts chemical cascade. Thromobplastin creates thrombin from prothrombin. Thrombin creates insoluble fibrin fron soluble firbrinogen. These strands tangle and trap blood, forming a clot.

Question 43

Why do only ateries get atherosclerosis?

Answer 43

Fast flowing and high pressure blood means a significantly greater chance of damage to the walls.

Question 44

Consequences of atherosclerosis.

Answer 44

Angina - chest pain. Fatty plaque ruptures - cholesterol released, rapid clot formation. Blocked blood supply.