,BIOL252/BIOL 252 Human Anatomy & Physiology II w/Lab
Module 3 Exam | Portage Learning | 2026 Edition (PDF)
1. Which layer of a blood vessel wall is composed of endothelial cells and provides a smooth surface to
minimize friction?
A) Tunica externa
B) Tunica media
C) Tunica intima
D) Tunica adventitia
Correct Answer: Tunica intima
Rationale: The tunica intima is the innermost layer of a blood vessel, lined by a simple squamous
epithelium called the endothelium, which reduces friction for blood flow. The tunica media contains
smooth muscle, and the tunica externa (adventitia) is the outer connective tissue layer.
2. Which tissue type is predominantly found within the tunica media of large arteries?
A) Dense irregular connective tissue
B) Smooth muscle and elastic fibers
C) Hyaline cartilage
D) Simple cuboidal epithelium
Correct Answer: Smooth muscle and elastic fibers
Rationale: The tunica media is the middle layer responsible for vasoconstriction and vasodilation,
containing varying amounts of smooth muscle tissue and elastic fibers depending on the artery type.
3. What is the name of the tiny blood vessels that supply blood to the walls of large blood vessels
themselves?
A) Vasa vasorum
B) Thoroughfare channels
,C) Anastomoses
D) Sinusoids
Correct Answer: Vasa vasorum
Rationale: Large blood vessels have walls too thick for nutrients to diffuse from the main lumen; the
vasa vasorum acts as a network of tiny vessels supplying these outer tunics.
4. Which of the following correctly describes the structural difference between arteries and veins?
A) Arteries have valves; veins do not
B) Veins have a thicker tunica media than arteries
C) Arteries have a thicker tunica media and more elastic tissue than veins
D) Veins are always larger in diameter than arteries
Correct Answer: Arteries have a thicker tunica media and more elastic tissue than veins
Rationale: Arteries have a thicker tunica media with more smooth muscle and elastic tissue to withstand
and regulate high pressure. Veins have thinner walls and contain valves to prevent backflow.
5. Which type of capillary is the most common and allows for the exchange of nutrients and gases?
A) Fenestrated capillaries
B) Sinusoids
C) Continuous capillaries
D) Discontinuous capillaries
Correct Answer: Continuous capillaries
Rationale: Continuous capillaries are the most common type, found in muscle, skin, and the central
nervous system. They have a continuous endothelial lining with small intercellular clefts that allow for
the exchange of water, ions, and small molecules.
, 6. Which type of capillary is characterized by large gaps in the endothelial lining and is found in the liver
and spleen?
A) Continuous capillaries
B) Fenestrated capillaries
C) Sinusoids
D) Metarterioles
Correct Answer: Sinusoids
Rationale: Sinusoids are the most permeable type of capillary, with large gaps between endothelial cells
and an incomplete basement membrane. They are found in the liver, spleen, and bone marrow, allowing
for the passage of large molecules and cells.
7. Which structure connects an arteriole directly to a venule, bypassing the capillary bed?
A) Thoroughfare channel
B) Precapillary sphincter
C) Sinusoid
D) Anastomosis
Correct Answer: Thoroughfare channel
Rationale: A thoroughfare channel is a direct connection between an arteriole and a venule that
bypasses the capillary network. It allows blood to flow directly through the capillary bed when
precapillary sphincters are closed.
8. The force exerted by blood against the wall of a blood vessel is called:
A) Osmotic pressure
B) Blood pressure
C) Hydrostatic pressure
Module 3 Exam | Portage Learning | 2026 Edition (PDF)
1. Which layer of a blood vessel wall is composed of endothelial cells and provides a smooth surface to
minimize friction?
A) Tunica externa
B) Tunica media
C) Tunica intima
D) Tunica adventitia
Correct Answer: Tunica intima
Rationale: The tunica intima is the innermost layer of a blood vessel, lined by a simple squamous
epithelium called the endothelium, which reduces friction for blood flow. The tunica media contains
smooth muscle, and the tunica externa (adventitia) is the outer connective tissue layer.
2. Which tissue type is predominantly found within the tunica media of large arteries?
A) Dense irregular connective tissue
B) Smooth muscle and elastic fibers
C) Hyaline cartilage
D) Simple cuboidal epithelium
Correct Answer: Smooth muscle and elastic fibers
Rationale: The tunica media is the middle layer responsible for vasoconstriction and vasodilation,
containing varying amounts of smooth muscle tissue and elastic fibers depending on the artery type.
3. What is the name of the tiny blood vessels that supply blood to the walls of large blood vessels
themselves?
A) Vasa vasorum
B) Thoroughfare channels
,C) Anastomoses
D) Sinusoids
Correct Answer: Vasa vasorum
Rationale: Large blood vessels have walls too thick for nutrients to diffuse from the main lumen; the
vasa vasorum acts as a network of tiny vessels supplying these outer tunics.
4. Which of the following correctly describes the structural difference between arteries and veins?
A) Arteries have valves; veins do not
B) Veins have a thicker tunica media than arteries
C) Arteries have a thicker tunica media and more elastic tissue than veins
D) Veins are always larger in diameter than arteries
Correct Answer: Arteries have a thicker tunica media and more elastic tissue than veins
Rationale: Arteries have a thicker tunica media with more smooth muscle and elastic tissue to withstand
and regulate high pressure. Veins have thinner walls and contain valves to prevent backflow.
5. Which type of capillary is the most common and allows for the exchange of nutrients and gases?
A) Fenestrated capillaries
B) Sinusoids
C) Continuous capillaries
D) Discontinuous capillaries
Correct Answer: Continuous capillaries
Rationale: Continuous capillaries are the most common type, found in muscle, skin, and the central
nervous system. They have a continuous endothelial lining with small intercellular clefts that allow for
the exchange of water, ions, and small molecules.
, 6. Which type of capillary is characterized by large gaps in the endothelial lining and is found in the liver
and spleen?
A) Continuous capillaries
B) Fenestrated capillaries
C) Sinusoids
D) Metarterioles
Correct Answer: Sinusoids
Rationale: Sinusoids are the most permeable type of capillary, with large gaps between endothelial cells
and an incomplete basement membrane. They are found in the liver, spleen, and bone marrow, allowing
for the passage of large molecules and cells.
7. Which structure connects an arteriole directly to a venule, bypassing the capillary bed?
A) Thoroughfare channel
B) Precapillary sphincter
C) Sinusoid
D) Anastomosis
Correct Answer: Thoroughfare channel
Rationale: A thoroughfare channel is a direct connection between an arteriole and a venule that
bypasses the capillary network. It allows blood to flow directly through the capillary bed when
precapillary sphincters are closed.
8. The force exerted by blood against the wall of a blood vessel is called:
A) Osmotic pressure
B) Blood pressure
C) Hydrostatic pressure
