Blood Vessels I

Question 1

What are the primary functions of blood vessels?

Answer 1

• Allow gas exchange: O2 supply to tissue & CO2 removal
• Carry nutrients
• Carry metabolic wastes
• Carry hormones and signaling substances
• Maintain tissue fluid

Question 2

What changes occur in blood vessels with age?

Answer 2

• Largest arteries grow until age 25
• Intima and media involved
• Media stiffens starting at age 30 (lipid & calcium accumulation)
• Atherosclerotic plaques in the intima
• Calcification of the media of muscular arteries
• Coronaries can be threatened by plaque by age 25

Question 3

Be able to identify the 3 tunics in a micrograph or section

Answer 3

Arteries and veins are composed of three tunics:

tunica interna

tunica media

tunica adventitia (externa)

Question 4

Pulmonary circulation =

Answer 4

right atrium & ventricle

Question 5

Systemic circulation =

Answer 5

= left atrium & ventricle

Question 6

Which are more muscular, arteries or veins?

Answer 6

arteries

Question 7

Tunica Intima

Answer 7

endothelium, basement membrane, subendothelial layer of loose CT, and an internal elastic lamina (in arteries)

Question 8

Tunica Media

Answer 8

smooth muscle, variable amounts of elastic fibers and lamellae, reticular fibers, proteoglycans, and external elastic lamina (+/-)

Question 9

Tunica Adventitia

Answer 9

fibroblasts, longitudinal collagen and elastic fibers, vasa vasorum (+/-)

Question 10

What are the 3 layers of the heart?

Answer 10

epicardium (outermost)

cardiac muscle = myocardium

endocardium (innermost)

Question 11

In elastic arteries, which layer is thickest?

Answer 11

tunica media is biggest

Question 12

Describe elastic arteries

Answer 12

Aorta and its main branches

Physical properties of elastic arteries produce a more uniform pressure and flow

Question 13

Describe Mixed or Musculo-Elastic Arteries

Answer 13

Parts of terminal abdominal aorta, iliac arteries, external carotids etc.

Transitional segments between elastic and muscular arteries

Large tunica adventitia

Question 14

Describe muscular arteries

Answer 14

Most named arteries are of this type

Wavy IEL

Question 15

Describe arterioles

Answer 15

Function to maintain blood pressure and reduce pressure ahead of capillaries

Question 16

Athlerosclerosis typically occurs @

Answer 16

Branch points

Question 17

Describe metarterioles

Answer 17

A Metarteriole (or arterial capillary[citation needed]) is a short vessel that links arterioles and venules.[1] Instead of a continuous tunica media, they have individual smooth muscle cells placed a short distance apart, each forming a precapillary sphincter that encircles the entrance to that capillary bed. Constriction of these sphincters reduces or shuts off blood flow through their respective capillary beds. This allows the blood to be diverted to elsewhere in the body.