SEHS Topic 2.2

Question 1

State the composition of blood.

Answer 1

A specialised type of connective tissue

Question 2

What are the 4 components of Blood?

Answer 2

• Erythrocytes (red blood cells)
• Leukocytes (white blood cells)
• Platelets
• Plasma

Question 3

How many % does Erythrocytes make up in the formed elements of blood?

Answer 3

Erythrocytes (red blood cells) make up 99% of the formed elements in the blood

Question 4

Determine Plasma.

Answer 4

Colorless fluid that contains water, protein and nutrients

Question 5

Distinguish the functions of Erythrocytes.

Answer 5

Erythrocytes (Red Blood Cells)
- Contain an oxygen-carrying pigment called hemoglobin (protein), which gives blood its red color
- Transport nutrients, oxygen, carbon dioxide, waste products and hormones to cells and organs around the body

Question 6

Distinguish the functions of Leukocytes.

Answer 6

Leukocytes (White Blood Cells)
- Help combat infection and inflammation
- They ingest foreign microbes

Question 7

Distinguish the functions of Platelets.

Answer 7

Platelets
- They are tiny pieces of cell which have no nucleus
- Are involved in the process of clotting to help repair blood vessels by using a
“meshwork” of fibers

Question 8

Describe the Heart.

Answer 8

Heart - an involuntary muscle with striated muscle fibers (myocardium). Atria - (left & right) receiving blood from the body. Have thin walls bc they only have to pump to the ventricles

Question 9

Describe the Atria (anatomy of the heart).

Answer 9

Atria - (left & right) receiving blood from the body. Have thin walls bc they only have to pump to the ventricles

Question 10

Describe the Ventricles (anatomy of the heart).

Answer 10

Ventricles - (left & right) they are thick as they propel blood from the heart to body

Question 11

Describe the Valves (anatomy of the heart).

Answer 11

Valves - prevent backflow by shutting when the heart relaxes
1. Atrioventricular valves (tricuspid & bicuspid/mitral) 2. Pulmonary and Aortic Semilunar Valve

Question 12

State the 4 valves of the Heart.

Answer 12

1. Atrioventricular valves (tricuspid & bicuspid/mitral)
2. Pulmonary and Aortic Semilunar Valve

Question 13

Describe the intrinsic regulation of heart rate and the sequence of excitation of the heart muscle.

Answer 13

Intrinsic

Pacemaker system
1. Starts in the right atrium
2. A cardiac impulse is initiated from the sino-atrial
(SA) node (pacemaker)
3. The impulse causes the atria to contract
4. Cardiac impulse reaches and activates the
atrioventricular (AV) node
5. This passes the impulse down Bundle of His (in
the septum of the heart)
6. Bundle of his splits left and right, up around the
heart (Purkinje fibers)
7. The impulse is spread around the walls of ventricles causing them to contract
8. Ventricles relax and the cycle starts again

Question 14

What does Pulmonary Circulation do?

Answer 14

Caries deoxygenated blood away from trhe heart to the lungs and returns oxygenated blood back to the heart

Question 15

What does Systemic Circulation do?

Answer 15

Carries oxygenated blood away from the heart to the body and returns deoxygenated blood back to the heart

Question 16

What is Heart Rate (HR)?

Answer 16

The number of times the heart beats per minute (bpm)

Question 17

What is Stroke Volume (SV)?

Answer 17

The amount of blood pumped by each ventricle per beat (liters)

Question 18

What is Cardiac Output (Q)?

Answer 18

The amount of blood pumped from the heart in one minute (liters)

Question 19

What is Basal Heart Rate?

Answer 19

When HR is reduced to a min (e.g. sleeping)

Question 20

What is the equation for Cardiac Output?

Answer 20

Cardiac Output = Stroke Volume x Heart rate

Q = SV x HR

Question 21

What is Venous Return?

Answer 21

The amount of blood returned meaning heart rate is increased

Question 22

How does Heart Rate differ for males and females?

Answer 22

Heart Rate is lower in males than females

Question 23

How does Stroke Volume differ for males and females?

Answer 23

Stroke Volume is lower in females than males (body size plays a role)

Question 24

How does Cardiac Output differ for males and females?

Answer 24

Same during rest and sub-maximal exercise, but trained have higher during maximal exercise

Question 25

How does Heart Rate differ for children and adults?

Answer 25

Heart Rate is higher in children than adults

Question 26

How does Stroke Volume differ for children and adults?

Answer 26

Stroke Volume is lower in children than adults

Question 27

How does Cardiac Output differ for children and adults?

Answer 27

Cardiac Output is smaller in children than adults

Question 28

Explain Cardiovascular drift.

Answer 28

Cardiovascular drift refers to the increase in heart rate that occurs during prolonged submaximal exercise with little or no change in workload.

During this, heart rate increases, stroke volume decreases but cardiac output remains the same.

Cardiovascular drift is mostly caused by increased body temperature. After 10-15 min of exercise body temperature will increase, the body will try to cool down by sweating.

A portion of this sweat comes from the plasma, causing the plasma volume to decrease.

The decrease in plasma volume will decrease venous return and stroke volume, and will cause the blood to become more viscous.

Staying hydrated will help reduce cardiovascular drift. Cardiovascular effect is increased in warmer climates.

Question 29

Define Systolic.

Answer 29

The force exerted by blood on the arterial walls during contraction

Question 30

Define Diastolic.

Answer 30

The force exerted by blood on arterial walls during relaxation

Question 31

Analyse systolic and diastolic blood pressure DURING REST.

Answer 31

• Systolic pressure is lower
• Diastolic pressure is lower

Question 32

Analyse systolic and diastolic blood pressure DURING EXERCISE.

Answer 32

• Systolic pressure is higher
• Diastolic pressure does not raise as much as systolic

Question 33

What is the Starling’s Law?

Answer 33

The more the heart fills during diastole, the greator the force of contractioin during systole

Question 34

Where will blood distribute to during exercise?

Answer 34

Muscles (87%)

Question 35

Where will blood distribute to during rest?

Answer 35

Organs e.g. (digestion)
Bone Marrow 5%
Brain 18%
Heart 5%
Liver 25%
Kidney 20%
Muscles 20%
Muscles 20%
Skin 7%

Question 36

Describe the cardiovascular adaptations resulting from endurance exercise training.

Answer 36

⟶ Resting heart rate decreases

⟶ Stroke volume/left ventricular volume increases
↳ because of heart hypertrophy

⟶ Increased capillarization
↳ the muscles are surrounded by an increase in capillaries that allow more oxygen supply

⟶ Arterio-venous oxygen difference increases
↳ this is due to adaptations in the mitochondria, increased myoglobin and improved capillarization

Question 37

what is VO₂ MAX?

Answer 37

The maximum amount of oxygen that can be consumed (millimeters)

⟶ those who have a higher fitness level have higher VO₂ max values and can exercise more intensely than those who are not as well conditioned.

Question 38

Discuss the variability of maximal oxygen consumption (VO2MAX) within AGE.

Answer 38

VO₂MAX decreases with age

Question 39

Discuss the variability of maximal oxygen consumption (VO2MAX) within Trained vs Untrained.

Answer 39

VO₂MAX higher in trained and lower in untrained

Question 40

Discuss the variability of maximal oxygen consumption (VO2MAX) within Male vs Female.

Answer 40

VO₂MAX higher in males than females

Question 41

Discuss the variability of maximal oxygen consumption with different modes of exercise.

Answer 41

When running on a treadmill, the

VO₂ max will be higher because more muscles are being

used, compared to arm ergometry where the participant is sitting down and only using their

arms, which requires less oxygen going to the muscles. However, oxygen than arm ergometry.

cycling requires more oxygen than arm ergometry.