8: Integration of cardiovascular mechanisms

Question 1

Generally, in the cardiovascular system, the heart acts as…

Answer 1

pump.

Question 2

What is the function of the arteries?

Answer 2

Carries blood from the heart to the tissues

Question 3

What is an important point about arterioles?

Answer 3

They are major resistance vessels

Question 4

What occurs in the capillary beds?

Answer 4

Site of exchange of gas, nutrients and water between blood and tissues

Question 5

Veins contain a (majority / minority) of blood volume during rest.

Answer 5

majority

Question 6

Veins act as ___ vessels.

Answer 6

capacitance

Question 7

Blood coming back to the heart from the veins is called the…

Answer 7

venous return.

Question 8

What are the three constituent parts of mean arterial pressure?

Answer 8

Heart rate (HR)

Stroke volume (SV)

Total peripheral resistance (TPR)

MAP = SV x HR x TPR

Question 9

Write an equation for pulse pressure.

Answer 9

Pulse pressure = Systolic BP - Diastolic BP

Question 10

What is an alternative way of calculating MAP?

Answer 10

MAP = Diastolic BP - (1/3rd of pulse pressure)

Question 11

What regulates total peripheral resistance?

Answer 11

Vascular smooth muscle

Question 12

What is the effect of vascular smooth muscle contraction?

Answer 12

1) ​Vasoconstriction
2) Increase in TPR
3) Increase in MAP (pressure upstream)

Question 13

What is the effect of vascular smooth muscle relaxation?

Answer 13

1) Vasodilatation
2) Decreased TPR
3) Decreased MAP

Question 14

Vascular smooth muscle is controlled by ___ and ___ means.

Answer 14

intrinsic , extrinsic

Question 15

Resistance to blood flow is mainly controlled by vascular smooth muscle through changes in the ___ of arterioles.

Answer 15

radius

Question 16

What factor is the most important in terms of resistance to blood flow?

Answer 16

Radius of arterioles

Question 17

Extrinsic control of vascular smooth muscle involves…

Answer 17

nerves and hormones.

Question 18

Which division of the nervous system supplies vascular smooth muscle?

Answer 18

Sympathetic nervous system

Question 19

What is the sympathetic neurotransmitter which acts on vascular smooth muscle to regulate blood pressure?

Answer 19

Noradrenaline

Question 20

In vascular smooth muscle, which receptor does noradrenaline act on?

Answer 20

α receptors

Question 21

Vascular smooth muscle is partially constricted at rest. What is this also known as?

Answer 21

Vasomotor tone

Question 22

What generates vasomotor tone?

Answer 22

Tonic discharge of sympathetic nerves resulting in continous release of noradrenaline

Question 23

What effect does increased sympathetic discharge have on vasomotor tone?

What effect will be seen in the vasculature?

Answer 23

Increases the vasomotor tone

causing vasoconstriction.

Question 24

What effect does decreased sympathetic discharge have on the vasomotor tone?

What effect does this have on the vasculature?

Answer 24

Decreases vasomotor tone

causing vasodilatation.

Question 25

Is the **parasympathetic division** involved in control of vascular smooth muscle?

Answer 25

No

Question 26

Where in the body ***is*** vascular smooth muscle innervated by the **parasympathetic nervous system**?

Answer 26

Penis Clitoris

Question 27

**\_\_\_** is involved in nervous control of vascular smooth muscle. **\_\_\_** is involved in hormonal control of vascular smooth muscle. (adrenaline, noradrenaline)

Answer 27

**Adrenaline** - hormonal **Noradrenaline** - nervous

Question 28

Effects of **adrenaline** on vascular smooth muscle is largely \_\_\_-specific.

Answer 28

**organ**

Question 29

Adrenaline is a hormone which acts on vascular smooth muscle. It has different effects depending on which organ it binds to, as each organ has different receptors. Arrange correctly: Adrenaline acting on _ receptors causes \_\_\_. Adrenaline acting on _ receptors causes \_\_\_. **α** , **β₂​** , **vasoconstriction** , **vasodilatation**

Answer 29

Adrenaline acting on **α​** receptors causes **vasoconstriction**. Adrenaline acting on **β₂** receptors causes **vasodilatation**.

Question 30

Where in the body are **α​ receptors** found?

Answer 30

Skin, gut and kidney **arterioles**

Question 31

Where in the body are **β​₂ receptors** found?

Answer 31

**Skeletal** and **cardiac muscle arterioles**

Question 32

The fact that the binding of adrenaline to receptors causes differing vascular effects in different parts of the body helps with **strategic redistribution** of **blood** during \_\_\_.

Answer 32

**exercise**

Question 33

Apart from adrenaline binding to **α​₂** receptors to produce **vasoconstriction**, which other hormones produce **this** effect?

Answer 33

**Angiotensin II** **ADH**

Question 34

**Intrinsic** control of **vascular smooth muscle** matches blood flow to the ___ needs of cells.

Answer 34

**metabolic**