Introduction to Vasculature

Question 1

What are the three major components of the cardiovascular system?

Answer 1

The heart, blood vessels and blood

Question 2

What is the major function of the cardiovascular system?

Answer 2

Transportation of: nutrients and oxygen, waste products, and hormones

Question 3

Approximately how many miles of blood vessels are there in the cardiovascular system and how many of those miles are capillaries?

Answer 3

60,000 miles total 50,000 miles are capillaries

Question 4

What are the four chambers in the heart?

Answer 4

Right atria and ventricle and left atria and ventricle

Question 5

What does the left side of the heart do in terms of the atrium and ventricle?

Answer 5

The left atrium receives oxygenated blood, and the left ventricle pumps blood to the systemic circuit

Question 6

What does the right side of the heart do in terms of the atrium and ventricle?

Answer 6

The atrium receives deoxygenated blood and the ventricle pumps blood for the pulmonary circuit

Question 7

What are the three major types of blood vessels?

Answer 7

Arteries, capillaries, and veins

Question 8

What is the best definition for an artery?

Answer 8

An artery carries blood away from the heart

Question 9

What is the best definition for a vein?

Answer 9

A vein carries blood towards the heart

Question 10

What is a capillary?

Answer 10

The smallest of blood vessels; thin wall, their main role is to allow the exchange of materials between the blood and body tissues

Question 11

The walls of blood vessels have how many layers or tunics and what are they?

Answer 11

Three; 1) tunica interna or tunica intima; 2) tunica media; 3) tunica externa or tunica adventitia

Question 12

What are the three parts of the tunica interna or the tunica intima?

Answer 12

a. endothelium (simple squamous); b. basal lamina; c. subendothelial layer

Question 13

What is the layer in between the tunica interna and the tunica media of arteries and some arterioles?

Answer 13

The internal elastic membrane

Question 14

Define the tunica media.

Answer 14

This layer is the middle layer and contains rings of smooth muscle cells responsible for vasoconstriction and vasodilation; can also contain sheets or lamellae or laminae of elastin

Question 15

Define the tunica externa.

Answer 15

This is in larger vessels and contains a vasa vasorum and a nervi vascularis

Question 16

In a cross section would a vein or artery be more collapsed or more open?

Answer 16

An artery would be more open and a vein would be more collapsed

Question 17

What is the thickest layer of an artery?

Answer 17

The tunica media

Question 18

What is the thickest layer of a vein?

Answer 18

The tunica externa

Question 19

Is a vein as thick as its corresponding artery?

Answer 19

No a vein will be thinner

Question 20

Is the lumen of an artery as large as its corresponding vein?

Answer 20

No the lumen of an artery will be smaller than its corresponding vein

Question 21

Describe elastic or conducting arteries.

Answer 21

(Large arteries) these are the largest in diameter arteries that are greater than 10 mm; walls contain large amounts of elastic fibers; allows arteries to expand and recoil; important vessels in helping to propel blood onward while ventricles are relaxing; elastic fibers function as pressure reserve

Question 22

Describe muscular or distributing arteries.

Answer 22

(Medium arteries) These arteries are medium sized arteries that are 2 mm to 10 mm; walls contain large amounts of smooth muscle; important in regulating the blood flow to specific body regions; smooth muscle cells in circular orientation and are responsible for vasoconstriction and vasodilation

Question 23

Describe small arteries.

Answer 23

0.1 mm to 2 mm in diameter; as many as eight layers of smooth muscle in their tunica media

Question 24

Describe arterioles.

Answer 24

Smallest diameter artery; 10 micometers - 100 micrometers in diameter; only one or two layers of smooth muscle in the tunica media

Question 25

What is the diameter of a capillary?

Answer 25

4 micrometers to 10 micrometers

Question 26

How many walls do capillaries have?

Answer 26

Two, endothelial membrane (nonkeritanized simple squamous epithelium) and its basal lamina

Question 27

What is the main role of capillaries?

Answer 27

To allow exchange of materials between the blood and body tissues

Question 28

What are the four types of veins?

Answer 28

Venules, small veins, medium veins, and large veins

Question 29

What are the two kinds of venules?

Answer 29

Postcapillary venule and muscular venule

Question 30

Describe a venule.

Answer 30

Smallest diameter veins (10 - 100 micrometers) and these receive blood from capillaries

Question 31

Describe a postcapillary venule.

Answer 31

Endothelial cell with basal lamina and pericytes; no tunica media and no adventitia

Question 32

Describe a muscular venule.

Answer 32

Possess a tunica media with one or two layers of smooth muscle and a thin tunica adventita, typically no pericytes here

Question 33

Describe small veins.

Answer 33

0.1 - 1 mm in diameter, receive blood from muscular venule

Question 34

Describe medium veins.

Answer 34

1 - 10 mm in diameter; all three layers present

Question 35

Describe large veins.

Answer 35

Larger than 10 mm in diameter; all three layers present

Question 36

The veins in limbs typically have valves that prevent back-flow, what part of the veins make up the valves?

Answer 36

The valves are thin folds of tunica intima or tunica interna- endothelial cells over a thin layer of connective tissue