Sue - The Heart

Question 1

Cardiac Output (Q) =

Answer 1

Stroke Volume (SV) x Heart Rate (HR)

Question 2

The amount of blood pumped out by the ventricle in each contraction

Answer 2

Cardiac Output

Question 3

The amount of blood pumped out by the left ventricle in each contraction

Answer 3

Stroke Volume

Question 4

The number of times the heart beats per minute

Answer 4

Heart Rate

Question 5

During exercise, cardiac output will…

Answer 5

increase until maximum intensity is reached and then it plateau’s

Question 6

When someone has a lower resting heart rate below 60 beats per minute

Answer 6

Bradycardia

Question 7

An increase in size and growth of skeletal muscles

Answer 7

Hypertrophy

Question 8

Why does Stroke volume increase while exercise does up to 40-60 % of maximum effort?

Answer 8

As once the performer reaches this point the ventricles do not have as much to fill up with blood due to an increased HR, causing a plateau

Question 9

Explain cardiovascular drift?

Answer 9

When there is an increase in heart rate and a decrease in stroke volume due to prolonged exercise in warm conditions
Caused by reduction of fluid in the blood plasma due to increase in sweating so the blood becomes more viscous and so HR decreases > poor hydration

Question 10

How does the the heart initiate a heart beat?

Answer 10

SAN > Atrial systole (contraction) > AVN > Bundle of His > Bundle branches > Purkinje fibres > Ventricular systole

Question 11

Starlings Law order?

Answer 11

1. Increased VENOUS RETURN (due to veins being squeezed during exercise)
2. Leads to a greater diastolic filling so the cardiac muscle is STRETCHED
3. More powerful force of contraction
4. which increases the EJECTION FRACTION
5. Increase in STROKE VOLUME

Question 12

A stress hormone that is released by the sympathetic nerves and cardiac nerve during exercise

Answer 12

Adrenaline

Question 13

What effect does Adrenaline have?

Answer 13

It stimulates the SAN which results in an increase in both SPEED and FORCE of contraction, thereby increasing cardiac output. More blood is pumped to the working muscles so they can receive more oxygen for the energy they need.

Question 14

A nervous system that stimulates the heart to beat faster

Answer 14

Sympathetic

Question 15

A nervous system that returns the heart to its resting level

Answer 15

Parasympathetic

Question 16

The part of the nervous system that consists of nerve cells that transmit information to and from the CNS

Answer 16

Peripheral Nervous System (PNS)

Question 17

The part of the nervous system that consists of the brain and the spinal cord

Answer 17

Central Nervous System (CNS)

Question 18

Detect an increase in blood CO2

Answer 18

Chemoreceptors

Question 19

Detect an increase in muscle movement

Answer 19

Proprioreceptors

Question 20

Detect a change/decrease in blood pressure

Answer 20

Baroreceptors

Question 21

What do receptors do?

Answer 21

Send impulses to the Medulla Oblongata (brain) which increases the impulses to the SAN via the sympathetic nervous system to increase HR

Question 22

Causes coronary arteries to become blocked or start to narrow by gradual build-up of fatty deposits

Answer 22

Coronary heart disease

Question 23

Puts extra strain on arteries and the heart - can increase the risk of a heart attack

Answer 23

High blood pressure

Question 24

Transports cholesterol in the blood to the tissues and they are linked to an increased risk of heart disease

Known as the ‘bad cholesterol’

Answer 24

LDL - low density lipoproteins

Question 25

Transports excess cholesterol back to the liver where it is broken down and lowers risk of developing heart disease

Known as the ‘good’ cholesterol

Answer 25

HDL - high density lipoproteins

Question 26

When the blood supply to part of the brain is cut off causing damage to brain cells so they start to die

Answer 26

Stroke

Question 27

How can regular exercise reduce the effect on heart disease?

Answer 27

• keeps the heart healthy and more efficient
• lowers LDL and increases HDL
• Can lower blood pressure by up to 5-10mmHg
• aids maintenance of a healthy weight to reduce the risk of stroke by 27%

Question 28

Name the four chambers of the heart?

Answer 28

Left atrium, Left ventricle, Right atrium, Right ventricle

Question 29

What are the two types of valve sin the heart and what are there purpose?

Answer 29

Atrio-ventricular valve (AV valve)
Semi-lunar valve
To prevent back-flow of blood

Question 30

During a game of rugby, describe how the sympathetic pathway controls heart rate during the game?

[4 marks]

Answer 30

1. During exercise proprioreceptors detect an increase in muscle movement
2. production of carbon dioxide
3. stimulates chemoreceptors also
4. Impulses sent tot he medulla oblongata and impulses are stimulated through the sympathetic system
5. to the SAN
6. so HR increases

Question 31

Explain how the increasing level of carbon dioxide in the blood raises heart rate?

Answer 31

1. Detected by chemoreceptors
2. impulse sent to the Medulla Oblongata
3. through the Sympathetic system
4. to the SAN which increases HR

Question 32

Which vein brings dexoygenated blood into the heart from the body?

Answer 32

Vena Cava

Question 33

Which artery takes blood towards the lungs from the heart?

Answer 33

Pulmonary artery

Question 34

Which vein brings oxygenated blood back tot he heart from the lungs?

Answer 34

Pulmonary vein

Question 35

Which artery carries blood away from the heart at high pressures to the essential areas that require it?

Answer 35

Aorta

Question 36

How is maximum heart rate calculated?

Answer 36

220 - age