[L3 Anatomy and Physiology] Section 1: The heart and circulatory system

Question 1

What is the myocardium?

Answer 1

The Cardiac muscle, which is the predominant tissue of the heart.

Question 2

How does the heart prevent unwanted backflow of blood into the chambers of the heart?

Answer 2

Using a number of valves

Question 3

The valves open and close in response to what?

Answer 3

Changes in pressure as the heart contracts and relaxes

Question 4

What are the main valves of the heart?

Answer 4

Atrioventricular (AV) valves and the Semilunar (SL) valves

Question 5

Where is the Atrioventricular (AV) valve located

Answer 5

The AV valves are located between the atria and the ventricles and prevent the back-flow of blood from the ventricles into the atria.

Question 6

Where is the Semilunar (SL) valve located

Answer 6

The SL valves are located at the base of the arteries leaving the heart (aorta and pulmonary artery).

Question 7

What is Coronary Circulation?

Answer 7

The circulation of blood to the heart

Question 8

The heart, like any other tissue, requires a

constant supply of what?

Answer 8

Oygen and Nutrients

Question 9

The right coronary artery supplies blood to which area of the heart?

Answer 9

Myocardium of the right ventricle

Question 10

The left coronary artery supplies blood to which area of the heart?

Answer 10

Myocardium of the left ventricle and posterior of heart.

Question 11

Blood supply to the tissues can be maintained despite vessels becoming damaged (due to heart desease), because of what?

Answer 11

Most regions of the heart are served by more than one branch of coronary arteries.

Question 12

What is ischaemia?

Answer 12

Reduction in blood flow

Question 13

What is Myocardial ischaemia and what can it cause?

Answer 13

Reduction in blood flow to the heart through coronary circulation and can result in a myocardial infarction (or a heart attack)

Question 14

Most heart problems can be attributed to poor coronary circulation as a result of?

Answer 14

Blood clots, fatty plaques building up in the coronary arteries or spasms in the smooth muscle of their walls

Question 15

Vascular disease is?

Answer 15

The narrowing of the blood vessels

Question 16

Vascular disease is one of the main causes of death in the developed world and it is caused by?

Answer 16

Inflammation in blood vessels, accumulation of mineral, protein and fat deposits, which create a build-up of plaques on vessel walls.

Question 17

What is atherosclerosis?

Answer 17

Hardening of the arteries

Question 18

Describe what happends when an atery becomes inflamed or damaged.

Answer 18

Plaque forms on the artery walls (as the body attempts to repair the artery using cholesterol, protein and mineral deposits).

(As the plaque build ups) The artery becomes thicker, harder and less elastic.

The artery is then narrower and less able to stretch in response to blood flowing through it (so blood flow/oxygen to tissues is reduced).

Question 19

Coronary atherosclerosis can be associated with what type of pain?

Answer 19

Chest pain on exertion that settles with rest

Question 20

Blood pressure is an expression of arterial blood flow and what?

Answer 20

The peripheral resistance the blood encounters as

it flows round the body

Question 21

What is total peripheral resistance and what happens to blood pressure when it increases?

Answer 21

The resistance the blood vessels offer to blood flow; the greater the resistance, the higher the blood pressure

Question 22

Express Blood Pressure as a formula.

Answer 22

BLOOD PRESSURE = CARDIAC OUTPUT X TOTAL PERIPHERAL RESISTANCE

Question 23

140-159/90-99 mmHg is classified as?

Answer 23

Stage 1 Hypertension

Question 24

130-139/85-89 mmHg is classified as?

Answer 24

High normal - Pre-hypertension

Question 25

What is the most common type of stroke?

Answer 25

Ischaemic stroke

Question 26

What is a thrombosis?

Answer 26

An obstruction of a blood vessel leading to the brain by a localised blood clot

Question 27

What is an embolism?

Answer 27

An obstruction due to an embolus – a detached blood clot – from elsewhere in the body

Question 28

What is a haemorrhagic stroke?

Answer 28

An intracranial bleed linked to an aneurysm (localized, blood-filled, balloon-like bulge in the wall of a weakened blood vessel).

Question 29

What is the short-term effect of exercise on systolic blood pressure?

Answer 29

A linear increase in systolic blood pressure (SBP)

with increasing levels of exertion.

Question 30

What is the short-term effect of exercise on diastolic blood pressure?

Answer 30

A slight decrease during exertion due to vasodilation, or it will remain unchanged.

Question 31

Individuals with hypertension may experience what effect on diastolic blood pressure, and why?

Answer 31

A rise in diastolic blood pressure as a result of an impaired vasodilatory response.

Question 32

What effect does heavy weight training and isometric exercise have on systolic and diastolic blood pressure?

Answer 32

Significantly increases both systolic and diastolic blood pressure.

Question 33

Why is it important for an individual not to hold

their breath when performing eavy weight training and isometric exercise?

Answer 33

To avoid the Valsalva effect -which can

drastically increase blood pressure and heighten the risk of a cardiovascular event such as a heart attack or stroke

Question 34

What are some long-term benefits of aerobic/endurance training on the cardiovasuloar system:

Answer 34

• A greater stroke volume, i.e. more blood pumped per beat.
• A lower relative exercise heart rate, which allows for greater performance potential.
• Stronger, more elastic arteries.
• Lower levels of bad cholesterol (LDL) and higher levels of good cholesterol (HDL).
• An improved blood supply to the body’s tissues.
• Higher levels of haemoglobin in the blood, which increases its oxygencarrying capacity.
• Improved aerobic capacity (VO2 max).
• Lower blood pressure in the long term.