Cardiovascular pressure and capacitance

Question 1

What are the 3 layers of the walls of blood vessels?

Answer 1

Tunica interna
Tunica Media
Tunica externa

Question 2

What does tunica interna have?

Answer 2

epithelial inner lining

endothelium, BM (collagen fibres) Internal elastic lamina (elastic fibres)

Question 3

What does tunica media have?

Answer 3

Elastic fibres and circular smooth muscle cells, arteries present

Question 4

What does tunica adventitia have?

Answer 4

Elastic and collagen fibres

support and vaso vasorum

Question 5

How many types of blood vessels are there?

Answer 5

5

Question 6

What are the 2 types of arteries?

Answer 6

Elastic conducting

Muscular distributing

Question 7

What do large arteries do?

Answer 7

propel blood while ventricles are relaxing - pressure reservoir

Question 8

What do medium size arteries do?

Answer 8

Transport blood over long distances with little drop in BP

Question 9

What are 3 layers of arteries?

Answer 9

Tunica interna - squamous epithelium BM Lamina
Thick tunica media smooth muscle
Tunica externa

Question 10

Describe Arterioles?

Answer 10

Thin tunica interna fenestrated elastic lamin dissappears at terminal end
tunica media - 2 layers smooth circle muscle
tunica externa - elastic and collagen
smaller than arteri

Question 11

Why are Arterioles important?

Answer 11

By vasoconstriction and vasodilation influence peripheral resistance and modify blood flow from arteries to capillaries - Resistance vessels

Question 12

What is the terminal end of the arteriole?

Answer 12

Metarteriole - tunica interna surrounded by loose smooth mc

Question 13

What is at the metarteriole capillary junction?

Answer 13

distalmost muscle cells from precapillary spincter monitor blood flow to capillar

Question 14

What is at the distal end of a vessel?

Answer 14

Thoroughfare channe; - provides direct route for blood from arteriole to venule bypassing capillaries

Question 15

What is Vasomotion?

Answer 15

Intermittent blood flow due to alternating contraction and relaxation of smc of metarterioles

Question 16

How do capillaries function?

Answer 16

Allow exchange of fluid and metabolites between blood circ system and tissue - are exchange vessles

Question 17

What do tissues with high and low metabolic rates have?

Answer 17

High rate (brain, liver, kidney) - abundance of capillaries
Low rate - (lining epi, cornea, cartilage) few capillaries

Question 18

What do venules do?

Answer 18

Collect blood from capillaries and consist of tunica interna and media with SMC

Question 19

What are the venule walls?

Answer 19

Porous and function as sites for exchange of nutrients and waste and WBC - merge steadily to form larger venules to form veins

Question 20

What do Veins do?

Answer 20

thin tunica interna and media , externa is a thick layer, large lumen
Take blood to heart

Question 21

What are low pressure vessels called?

Answer 21

Capacitance vessels

Question 22

How much of bodys blood is in veins?

Answer 22

64% - rest are capillaries and arteries

Question 23

What are blood reservoirs?

Answer 23

Veins and Venules

Question 24

What are the 3 routes where substances enter or leave the capillaries?

Answer 24

diffusion, transcytosis and bulk flow

Question 25

What occurs in diffusion?

Answer 25

involved with flow of materials in and out of the capillaries -movement from high conc to low conc

Question 26

What occurs in transcyotsis?

Answer 26

Small materials transported across capillary walls encapsulated within invaginations of serosal membrane (pinocytosis) transport to release by exocytosis- large hydrophilic insulin transported

Question 27

What is bulk flow?

Answer 27

body fluid derived from ingested water and stored in blood plasma and intersitial fluid - fluid flows from blood to tissues via filtration

Question 28

what does movement of blood fluids depend on?

Answer 28

blood hydrostatic pressure BHP | Interstitial fluid osmotic pressure IFOP

Question 29

What happens in reabsorption?

Answer 29

pressure driven movement from interstitial fluid into blood capillaries depends on blood colloid osmotic pressure BCOPand in less on interstitial fluid hydrostatic pressure IFHP the flow of fluid from blood to tissues and back depends on forces of net filtration pressure NFP

Question 30

What % of fluid is filtered out of capillaries is reabsorped?

Answer 30

85% excess fluid enters lymph capillaries

Question 31

What is Oedema?

Answer 31

Increased in the interstitial fluid volume noticeable when fluid increased by 30%

Question 32

What happens with excess filtration?

Answer 32

Oedema caused by increase capillary BP and IFOP

Question 33

What happens with inadequate reabsorption?

Answer 33

Decrease in conc of plasma proteins and kidney disease