Lecture 6 - Cardiovascular

Question 1

Answer 1

Question 2

Answer 2

Question 3

How many layers if blood vessel wall

Answer 3

3

Question 4

What are the layers of the blood vessels called

Answer 4

1. Tunica itima (inner most)
2. Tunica Media
3. Tunica Adventitia (externa)

Question 5

Tuna intima strucutre

Answer 5

• lined by endothelium - a simple squamous epithelium which lines the lumen of all vessels (barrier between blood and wall - stops clottting)
• subendothelium - a sparse pad of loose FCT cushioning the endothelium
• internal elastic laminate (IEL) - a condensed sheet of elastic tissue. The IEL is well developed in arteries and less developed in veins.

Question 6

Histology of artery - intima and internal elastic lamina

Answer 6

Question 7

Tunica media structures

Answer 7

• smooth muscle
• variable content of connective tissue fibres - mainly elastin and collagen
• thickness of the media is proportional to both vessel diameter and blood pressure (high pressure = thick)

Question 8

Media

Answer 8

Question 9

Features of tunica adventitia (externa)

Answer 9

• loose FCT with a high content of collagen and variable amount of elastin
• in larger vessels, the adventitia contains the vasa vasorum (small blood vessels that supple the blood vessel wall)
• lymphatics and autonomic nerves are also found in this region (sympathetic fibres in smooth muscle - contagion of wall)

Question 10

Thickest layer in arteries

Answer 10

• tunica media

Question 11

Layer diagram

Answer 11

Answer 12

• circumficanlyl orientated cells
• tow diff types of stains showing diff things

Question 13

Vasa vasorum

Answer 13

• small artieries and veins
• supplies cells further from the lumen
• needed in big arteries

Question 14

Aorta wall muscle vs leg

Answer 14

• elastic artery
• has lots of elastic tissues
• media dominated by smooth tissue in tunica Media in femoral (mascular) artery
• when blood comes out of heart and into aorta it is high pressure and pulsating
• by making artery rubbery, it stretches and recoils with each pulse - making the difference in pressure between diastolic and systolic pressure similar - helps push blooofd too
• in peripheral vessels - change strucutre by uttering dirubution of blood - capillary Kim it

Question 15

Arteriole

Answer 15

Smallest artery

Question 16

Function of the arteriole

Answer 16

The resistance vessels of the circulation - determine blood pressure

• arteriole form resistance bed
• depending on state of contraction it supplies more or less resistance to push blood into supply path

Question 17

Function of capillaries

Answer 17

• site of exchange between blood and tissues

Question 18

Venules

Answer 18

• smallest veins
• first part of Venus grainage
• has veins to ensure blood goes in one direction
• deoxygenated blood flows in after capillaries

Question 19

Function of veins

Answer 19

• low pressure, large volume transport system
• one way (unidirectional) flow
• capacitance vessels - ability to hold excess fluid in times of need

Question 20

Hidtilogical strucutre of veins

Answer 20

• irregular, flattened shape with large Lyman and thin wall
• have spare capacity (can take up extra blood volume) = capacitance vessels
• three layers

Question 21

3 layers of veins

Answer 21

• intima
• media - much thinner then arteries - a few layers of smooth muscle (often in two distinct layers)
• adventitia - thickest layer of vein - collagen controls how much it extends

Question 22

Thickest layer of artery

Answer 22

Media

Question 23

Vein histology

Answer 23

Question 24

Vascular bundle

Answer 24

-two veins as needs double CSA to compensate for lower speed

Question 25

Varicus veins

Answer 25

• if skeletal muscle surrounds = deep
• large pressure at bottom of veins as a result of faulty veins