Blood Vessels (Webber)

Question 1

What are the components of blood vessels

Answer 1

Elastic fibres
Smooth muscle
Collagen
Endothelium

Question 2

Elastic fibres

Answer 2

These are composed of elastin and can stretch and recoil providing vessel walls with flexibility

Question 3

Elastic fibres in the artery’s

Answer 3

• Elastic fibres enable them to withstand the force of blood pumped out by the heart and stretch, to within the limits of the collagen, to take the larger blood volume
  Helps maintain pressure

Question 4

Elastic fibres in veins

Answer 4

Very little elastic fibres as pressure is not as high and does not have to be maintained

Question 5

Smooth muscle

Answer 5

Contacts or relaxes which changes the size of the lumen

Question 6

Endothelium

Answer 6

Lines the artery

Is very smooth so blood can flow easily over it

Question 7

Why is lumen of veins large

Answer 7

Veins hold a large reservoir of blood, up to 50% of blood volume is held in the veins

Question 8

Collagen

Answer 8

provides structural support to maintain shape and volume of the vessel

Question 9

Why do veins have no pulse

Answer 9

As the surges from the heart pumping are lost as the blood passes through the narrow capillaries

Question 10

Functions of capillaries

Answer 10

Link arterioles with venules

Substances are exchanged between tissue walls and the blood

Question 11

Function of arterioles

Answer 11

Link the arteries and the capillaries
More smooth muscle and less elastin in their walls as they have little pulse surge
Can constrict or dilate to change blood flow

Question 12

Function of Venules

Answer 12

Blood travels from the capillaries to the veins via venules

Question 13

Features of veins

Answer 13

Majority of veins have one way valves to stop back flow
Many of the bigger veins run between the bug active muscles so when the muscles contract blood is force to the head
Breaking movements of the chest act as the pump, pumping blood towards the heart