Week 4

Question 1

What is the cardiac cycle

Answer 1

All the mechanical and electrical events that occur during a single heartbeat

Question 2

Diastolic phase

Answer 2

Relaxation phase

The chambers of the heart fill with blood

Question 3

Systolic phase

Answer 3

Contraction phase

The ventricles contract and pump blood out of the aorta and pulmonary artery

Question 4

Stroke volume

Answer 4

The volume of blood pumped from the ventricles per beat

Question 5

Cardiac output

Answer 5

The amount of blood the heart pumps per minute

Question 6

Blood vessels have 3 layers

Answer 6

Tunica intima
Tunica media
Tunica externa

Question 7

Capillaries do not change size

Question 8

Intrinsic (local) control of blood vessel size

Answer 8

Stretch, temperature and chemicals

Vasoconstriction

Vasodilation

Question 9

Extrinsic control of blood vessel size

Answer 9

Autonomic nervous system and endocrine system

Question 10

Vasoconstriction occurs in response to

Answer 10

Cold
Increased 02
Decreased C02
Decreased hydrogen

Question 11

Vasodilation occurs in response to

Answer 11

Heat
Decreased 02
Increased C02
Increased hydrogen

Question 12

What is muscular pump

Answer 12

Skeletal muscles squeeing blood in the veins to increase venous return

(Benefit of a warm down)

Question 13

How much of the body’s mass is blood

Answer 13

8%

Question 14

Blood content

Answer 14

55% plasma
45% cellular content

Question 15

What are erythrocytes

Answer 15

(red blood cells) Contains a protein called haemoglobin, which carries oxygen from the lungs to all parts of the body

Question 16

Where are erythrocytes made

Answer 16

Bone marrow

Question 17

What is the life of an erythrocyte cell

Answer 17

4 months

Question 18

What is erythropoietin

Answer 18

Transported through plasma where it is transported to the bone marrow to increase production of red blood cells

Question 19

Where is erythropoietin produced/released

Answer 19

Kidneys

Question 20

How many 02 molecules can 1 haemoglobin carry

Answer 20

4

Question 21

How much oxygen in 1 litre of blood

Answer 21

200ml

197ml in haemoglobin
3ml in plasma

Question 22

What is the oxygen dissociation curve

Answer 22

The relationship between haemoglobin saturation with oxygen and partial pressure of oxygen

Question 23

What does an S-shaped curve represent

Answer 23

Changing affinity to oxygen

Question 24

What are the 3 ways that carbon dioxide is transported throughout the body

Answer 24

Dissolved in solution
Bicarbonate ions
Bound to haemoglobin

Question 25

What detects a change in blood PH

Answer 25

Chemoreceptors