Chapter 21: Blood Vessels & Circulation

Question 1

What is the Tunica Media layer of blood vessles?

Answer 1

Middle layer
- smooth muscle
- elastic connective tissue
- thickest layer in arteries
- controlled by sympathetic nervous syst.

Question 2

What is the Tunica Intima layer of blood vessels?

Answer 2

Innermost layer

Question 2

What is the Tunica Externa layer of blood vessels?

Answer 2

Outermost layer
- connective tissue
- thickest layer in veins

Question 3

What is the Lumen area of blood vessels?

Answer 3

Inner area inside Tunica Intima

Question 4

What is the function of Arteries?

Answer 4

carries blood away from heart

Question 5

What is the function of capillaries?

Answer 5

interact w interstitial fluid and blood from arteries
- move blood from arteries to veins

Question 6

What is the function of veins?

Answer 6

bring blood back to the heart

Question 7

Characteristics of Arteries

Answer 7

• thicker walls - Tunica Media thickest layer
• manage higher BP
• more structure
• elastic

Question 7

What are arterioles?

Answer 7

• smallest arteries

Question 8

Characteristics of Veins

Answer 8

• manage lower BP
• thinner walls
• have valves –> prevent backflow

Question 9

What are the two types of arteries?

Answer 9

• elastic
• muscular

Question 10

What is the function of contractile muscles in arteries?

Answer 10

help change diameter
- vasoconstriction: stimulation
- vasodilation: relaxation

Question 11

What are elastic arteries?

Answer 11

• arteries closest to heart
  -ex. aorta, pulmonary trunk
• “conducting”
• have large lumens –> less resistance
• stretches during ventricular systole
• recoils during ventricular diastole

Question 11

Arteriosclerosis

Answer 11

build up of plaque in arteries
- hardening of arteries

Question 12

Atherosclerosis

Answer 12

fatty deposits in tunica media

Question 13

Aneurism

Answer 13

ballooning of tunica externa
- leads to rupture and internal bleeding

Question 14

Bypass

Answer 14

artery or vein used to bypass narrowing of artery

Question 14

Angioplasty

Answer 14

insertion of catheter and balloon into artery
- balloon inflates, expanding stent
- balloon is deflated and taken out w stent left behind
- stent hold artery open for blood flow

Question 15

What are muscular arteries?

Answer 15

• “distributing”
• medium
  - ex. brachial, femoral, external carotid
• have thick tunica media
• help distribute blood to skeletal muscles and organs
• diameter can change

Question 16

What are arterioles?

Answer 16

• smallest vessels
• thin tunica media
• vasomotor tone regulated by medulla oblongata
• diameter changes determined by…
  - oxygen lvls
  - change in resistance

Question 17

What are capillaries?

Answer 17

vessels that help move blood from arteries to veins
- interact interstitial fluid & blood tg
- very thin tunica intima
- slow blood flow

Question 18

Function of capillary beds

Answer 18

• microcirculation: blood flow btwn arterioles and venules
• area of capillaries