Blood Vessels Flashcards Preview

Anatomy & Physiology > Blood Vessels > Flashcards

Flashcards in Blood Vessels Deck (54):
0

What blood vessels are part of the systemic circulation?

Aorta, arteries, arterioles

1

What vessels are part part of the pulmonary circulation?

Great veins, veins, venules

2

What vessels are part of both the pulmonary & systemic circulation?

Capillaries

3

What are the properties of the aorta?

Elastic artery, walls contain many many elastic fibres, elastic recoil during diastole helps to maintain high pressure during relaxation phase of cardiac cycle

4

What type of tissue are arteries made from?

Smooth muscle

5

What controls the arteries?

Autonomic nervous system

6

What do artery walls contain?

Thick layer of smooth muscle, small amount of elastic fibres

7

Arterioles are also muscular & are the principal site of what?

Vascular resistance

8

Arterioles are distribution vessels. What do they supply blood to?

Capillaries

9

What alters the diameter of the arterioles?

Autonomic nerves & hormones

10

What causes vasoconstriction in most arterioles?

Sympathetic stimulation & adrenaline

11

What are capillaries?

Exchange vessels running deep within tissues

12

What are capillaries often referred to as?

Capillary beds

13

What does the intricate network of capillaries provide?

Enormous surface area over which exchange can take place

14

Why is exchange possible in capillaries?

Walls are 1 cell thick

15

What is the purpose of the venous circulation?

Return blood to heart under low pressure

16

What are the properties of a vein?

Thin walls, wide lumen, some have valves to stop back flow

17

What aids venous return?

Locomotion (muscle pump) & breathing (respiratory pump)

18

What fibres are found in the pulmonary trunk & arteries?

Elastic

19

What fibres are found in the pulmonary arterioles?

Muscle

20

What are the pulmonary capillaries adapted for?

Exchange

21

What do the pulmonary venules do?

Collect blood from capillaries

22

What do pulmonary veins have?

Thin walls

23

Define blood pressure?

Blood pressure is the force exerted by the blood on the walls of the blood vessels.

24

Why do we measure blood pressure?

To check it is in the correct range for that person.
Establish a baseline against which to compare.

25

What should blood pressure be high enough to maintain?

Blood flow to brain. But not so high that vessels are damaged.

26

What generates blood pressure?

Pumping action of the heart.

27

Where are blood pressures highest?

Aorta & large arteries

28

What happens as blood flows around the circulation?

Pressure falls progressively

29

Where is blood pressure lowest?

Great veins as bod returns to right atrium

30

Where is blood pressure normally measured?

Systemic arteries

31

Where is bp most often measured clinically?

Brachial artery (large arteries)

32

Define systemic arterial blood pressure?

Systemic arterial blood pressure is the force exerted by the blood against the walls of the systemic arteries

33

In what fashion does blood flow in arteries?

Pulsatile

34

What causes fluctuations in arterial pressure?

Phase of the cardiac cycle

35

When is it called when bp at its highest?

Systolic pressure

36

What is it called when bp is at its lowest?

Diastolic pressure

37

Define systolic?

The force exerted by the blood on the walls of the systemic arteries during heart contraction

38

Define diastolic?

The force exerted by blood on the walls of the systemic arteries during heart relaxation

39

What is bp measured in?

mmHg (milimetres of mercury) / SI units (pascals/kilopascals)

40

How many mmHg is 1 kpa?

7.5mmHg

41

Define pulse pressure?

Difference between. Systolic & diastolic pressure ( systolic - diastolic)

42

What is a normal bp for a healthy adult?

120/80mmHg

43

What can influence bp?

Age, gender, genetics, diet, weight, stress, smoking etc...

44

What is hypertension?

High blood pressures & can damage vessells

45

What is hypotension?

Low pressures. Can cause dizziness

46

What characteristics of the cardiovascular system determine systemic arterial bp?

Cardiac output, resistance to blood through arteries

47

What is the equation for bp?

Blood pressure = cardiac output x pressure

48

What causes resistance to blood flow?

Diameter of blood vessels (influences by the autonomic nervous system & hormones).
Overall length of blood vessels.
Viscosity of blood.

49

Short term regulation of systemic arterial blood pressure is brought about by what?

Negative feedback loop

50

What receptors sense stretch/pressure in relation to bp?

Baroreceptors

51

Where are baroreceptors located?

Carotid sinus & aortic arch

52

What is the integrator related to bp?

Medulla oblongata

53

What are the effectors for bp?

Vasoconstriction/vasodilation, heart rate