B7.2 : Blood pressure, exercise, and Coronary Heart Disease Flashcards
1
Q
Exercise Recovery
A
A person’s physical fitness affects how quickly their pulse (heart rate) & breathing rate recover (return to normal) after exercise.
2
Q
Testing Exercise Recovery
A
- Record someone’s pulse (beats per minute) and breathing rate (breaths per minute) while they’re sitting down.
- Measure their pulse and breathing rate again straight after they have done 4 minutes of intense exercise.
- Measure again two minutes later. Have their pulse and breathing rates returned to normal?
3
Q
Effects of exercise
A
- Muscle cells use up more energy (released in respiration) during exercise, so they need to respire at a faster rate.
- Breathing rate increases to take in more oxygen and to get rid of the carbon dioxide produced by respiration.
- The heart pumps faster to circulate oxygenated blood to muscle tissues.
- The heart rate and breathing rate of fit people return to normal faster after exercise than those of less fit people.
- Less lactic acid (from anaerobic respiration) builds up in the muscles of fitter people.
4
Q
Blood pressure
A
- As the ventricles of the heart contract, they force blood at high pressure into the arteries
- This pressure needs to carry blood to the working tissues, but it must not be so high that it damages the blood vessels
- Blood pressure can be varies such as to force more blood to muscles during exercise
5
Q
How to raise blood pressure
A
- making the ventricles contract more powerfully
- Narrowing the diameter of the arteries
- Stress or excitement also raise the blood pressure
- A diet with too much saturated fat can cause high blood pressure by clogging up the arteries
6
Q
Measuring blood pressure
A
- The blood pressure naturally goes up and down during the heart’s cycles of contraction and relaxation
- The blood pressure is highest when the ventricles contract (systolic pressure) and lowest when the heart walls are relaxed as blood returns into the atria (diastolic pressure)
7
Q
Supply of blood to the heart muscle
A
- Heart muscle contracts to push blood through the vessels of the circulation
- This contraction requires energy which is made available by aerobic respiration, so the working cells of the heart need glucose and oxygen for respiration
- The blood passing through the chambers on the left side of the heart carries oxygen and glucose, but the heart cells cannot use these because the muscular walls are very thick and the blood is too far away
- The heart muscle has its own blood supply, delivered to capillary beds in the walls of the heart through the coronary arteries.
- The coronary arteries branch off from the aorta, just where the aorta leaves the left ventricle
- The heart therefore has a high-pressure supply of blood loaded with oxygen and glucose
- Once these useful substances have been removed by the heart muscle cells and replaced with wastes such as carbon dioxide, the blood returns to the circulation through coronary veins which pour blood into the vena cava
8
Q
Risk factors of coronary heart disease
A
- Smoking
- lack of exercise
- being overweight
- a diet high in saturated fats
- being male
- being over 40 years old and having a genetic predisposition
9
Q
Coronary heart disease tunnel explanation
A
- Imagine people carrying wood to a fire through a tunnel.
- If the tunnel narrows, fewer people can fit through the tunnel.
- This means that the fire will start to die out as less wood can reach it.
10
Q
Coronary Heart disease
A
- The muscle cells in your heart need glucose and oxygen to carry out respiration to allow your heart muscles to keep contracting.
- Glucose and oxygen are transported to the heart in the coronary arteries.
- If they become blocked it can cause muscles to be starved of oxygen and these cells die. This could cause a heart attack.
- Healthy arteries are smooth, letting blood flow easily. However cholesterol which is made in the liver, can stick to their walls.
11
Q
Atheroscelorosis
A
- Cholesterol narrows (makes it thinner) the artery and slow down the blood. This condition is called atherosclerosis.
12
Q
Thrombosis
A
The artery walls become rough which can cause the blood to clot (stick together) and block the blood vessel. The blockage is called thrombosis..
13
Q
Angina
A
- If the artery gets partly blocked it can cause chest pains, especially when the heart is working more e.g. activity or emotions.
- This chest pain is called ANGINA. Caused by not enough oxygen getting to the muscle.
- Angina could represent as a warning that a person is at greater risk of a heart attack.
14
Q
Cardiac arrest
A
- If there is a total blockage this can cause a heart attack.
- The heart cannot get enough oxygen, this causes severe pain in the chest and part of the heart is damaged / dies.
- It may stop beating completely, this is known as CARDIAC ARREST.
- Death will follow if heart does not start beating again.
15
Q
Reducing your chances of getting CHD
A
- Take care of your diet
- Eat more poultry and fish
- Cut down on fried foods
- Eat less red meat
- Eat more fruit and veg
- Do regular exercise
- Do not smoke.
