17: Blood Vessels

Question 1

What are the three primary layers that form blood vessels from external to internal?

Answer 1

Tunica externa
Tunica media
Tunica intima

Question 2

What layer of the tunica intima is composed of simple squamous epithelium?

Answer 2

Endothelium

Question 3

What layer of the tunica intima binds the endothelium to a layer of areolar connective tissue?

Answer 3

Basement membrane

Question 4

What layer forms the boundary between the tunica intima and tunica media in larger arteries?

Answer 4

Internal elastic membrane (not present in veins)

Question 5

What layer of blood vessels is much thicker in arteries than veins and is composed of layers of smooth muscle?

Answer 5

Tunica media

Question 6

What layer forms the boundary between the tunica media and the tunica externa in larger arteries?

Answer 6

External elastic membrane (not present in veins or smaller arteries)

Question 7

What layer of blood vessels is composed primarily of collagenous fibers and is normally the thickest layer in veins?

Answer 7

Tunica externa

Question 8

What structure do large blood vessels have to supply blood to walls of the same blood vessels?

Answer 8

Vaso vasorum

Question 9

What is the difference of the appearance of the tunica intima in arteries and veins?

Answer 9

In arteries the tunica intima is wrinkled because of vasodilation and vasoconstriction

Question 10

What is an elastic artery?

Answer 10

Arteries closest to the heart that have a high percentage of elastic fibers in all three of their tunics

Question 11

What is a muscular artery?

Answer 11

An artery with a decreased amount of elastic fibers but an increased amount of smooth muscle in the tunica media

Question 12

Which of the normal three layers of blood vessels do arterioles have?

Answer 12

ALL OF THEM! Trick question lol

Question 13

What are the 3 types of capillaries?

Answer 13

Continuous
Fenestrated
Sinusoidal

Question 14

What characteristic in continuous capillaries allow for exchange of small molecules?

Answer 14

Intercellular clefts are portions of tight junctions that are incomplete

Question 15

What characteristic of fenestrated capillaries allows for exchange of large molecules?

Answer 15

Pores in the capillary

Question 16

What kind of capillary is least common?

Answer 16

Sinusoidal

Question 17

What characteristic of sinusoidal capillaries allows for passage of whole cells?

Answer 17

Extensive intercellular gaps and incomplete basement membranes

Question 18

What is a metarteriole?

Answer 18

Portion between arterioles and capillaries that has characteristics of both, with incomplete smooth muscle rings

Question 19

What structure regulates blood flow between metarterioles and capillaries?

Answer 19

Precapillary sphincters

Question 20

What is the smallest portion of a vein (analogous to arterioles)?

Answer 20

Venules

Question 21

What does the umbilical vein carry?

Answer 21

Oxygen-rich blood

Question 22

What do the 2 umbilical arteries carry?

Answer 22

oxygen-depleted blood

Question 23

What structure carries the blood from the umbilical vein to the inferior vena cava?

Answer 23

Ductus venosus

Question 24

What structure in adults is the remnant of the umbilical arteries?

Answer 24

Medial umbilical ligaments

Question 25

What structure in adults is the remnant of the umbilical vein?

Answer 25

Round ligament of the liver

Question 26

How many circulatory shunts are there in a fetus? What do they do?

Answer 26

3 2 of them divert blood from the pulmonary to the systemic circuit 1 connects the umbilical vein to the inferior vena cava

Question 27

What is the foramen ovale? What does is become in adults?

Answer 27

An opening in the interatrial septum that allows blood to flow from the right to the left atrium Becomes the fossa ovalis

Question 28

What is the ductus arteriosus? What does it become in adults?

Answer 28

Muscular vessel that connects the pulmonary trunk to the aorta. This diverts most of the blood from the pulmonary trunk to the aorta (only leaving enough blood to keep lung tissue alive) Becomes the ligamentum arteriosum

Question 29

What is the ductus venosus? What does it become in adults?

Answer 29

Vein from the umbilical vein that bypasses the fetal liver sinusoids and goes directly to the inferior vena cava Becomes ligamentum venosum

Question 30

How does atherosclerosis occur?

Answer 30

Injury to the endothelium of an artery (could be from high blood glucose, infection, tobacco, etc.) that irritates and scars the endothelium. Cholesterol and other cellular debris get trapped in the scarring causing a buildup of plaque, or atheroma. Plaque can break off and become embolus

Question 31

What are varicose veins?

Answer 31

Veins with defective valves that allow blood to accumulate in the veins