Arterioles,Veins,Veins

True or False

Arteries,Veins and Artrerioles all have the same basic layered structure

True!

They all have tough fibrous outer layer, muscle layer, elastic layer, thin endothelium and lumen

Which type of blood vessel transport blood towards the heart

a. Veins

b. Arteries

c. Arterioles

A!

Veins transport blood to the heart (usually at a low pressure)

What type of blood vessel is shown in this picture?

Please state your reasoning

It is a vein, it has a thin layer of elastic layers and muscle layers and has a wide lumen

This is an artery with a smaller lumen and a thicker muscle and elastic layers.

Please explain how its structure relates to its function

* Arteries must be able to withstand high pressures generated by the contracting heart, and maintain these pressures when the heart is relaxed
* **the wall of the artery is relatively thick** with layers of collagen, smooth muscle and elastic fibres


* The elastic fibres allow the artery wall to expand around blood surging through at high pressure when the heart contracts, these fibres then recoil when the heart relaxes – this alongside a narrow lumen maintains high blood pressure

Lumen

Which blood vessel carries blood from arteries to capillaries

a. Veins

b. Arteries

c. Arterioles

C!

Arterioles

True of False

The overall thickness of a vein is thicker than the muscle layer of an artery

False!

The overall thickness of veins is thinner than in arteries the pressure in theveins

True or False

Veins have valves at intervals throughout

True, these ensure that blood does not flow backwards which it might otherwise because pressure is so low. The valves ensure the blood flow in one direction only.

Why is the elastic layer in arterioles thinner than it is in arteries:

\
a. Because pressure is higher

b. Because pressure is lower

c. It is not thinner, it is the same size

B!

Because pressure is lower

Which blood vessel transports blood from the arteries to the capillaries

\
a. Arteries

b. Veins

c. Arterioles

C!