Match each vascular structure to its function or characteristic. Terms may apply to more than one question. Some terms may not be used.
a.arteries
i.sinusoids
b.tunica externa
j.tunica media
c.capillaries
k.capacitance vessels
d.tunica intima
l.distributing arteries
e.lumen
m.conducting arteries
f.resistance vessels
n.metarterioles
g.medium-sized veins
o.large veins
h.venules
p.arterioles
-The coronary arteries arise from which major artery?
A) Ascending aorta
B) Left subclavian artery
C) Common carotid artery
D) Brachiocephalic artery

Question

Quizplus · Accepted Answer

The coronary arteries arise from the ascending aorta, just above the aortic valve.

Answer: A, M
 Arteries can be classified as either conducting arteries or distributing arteries based on their size and function. Conducting arteries, such as the aorta and pulmonary trunk, are the largest arteries in the body and function to conduct blood away from the heart. Distributing arteries, such as the brachial and femoral arteries, are smaller vessels that distribute blood to specific regions or organs.

Answer: D
 The tunica externa (also known as tunica adventitia) is the outermost layer of a blood vessel, composed mainly of collagen fibers. It functions to provide support and protection to the vessel.

Answer: C
 Capillaries are the smallest and thinnest blood vessels in the body, with a diameter just large enough for red blood cells to pass through in single file. Their thin walls allow for rapid exchange of gases, nutrients, and waste products between the blood and surrounding tissues.

Answer: D
 The tunica intima (also known as tunica interna) is the innermost layer of a blood vessel, composed of endothelial cells and a thin layer of connective tissue. It functions to provide a smooth surface for blood flow and to regulate vascular tone.

Answer: F
 Resistance vessels, including arterioles and pre-capillary sphincters, function to regulate blood flow and blood pressure by changing the diameter of the vessel lumen.

Answer: G
 Medium-sized veins, such as the radial and ulnar veins, function to transport blood from the capillary bed back to the heart. They have thinner walls than arteries and less smooth muscle in their tunica media.

Answer: I
 Sinusoids are a type of capillary found in certain specialized organs, such as the liver and spleen. They have large gaps between the endothelial cells that allow for the passage of large molecules, including blood cells and plasma proteins.

Answer: J
 The tunica media is the middle layer of a blood vessel, composed mainly of smooth muscle cells and elastic fibers. It functions to regulate vascular tone and diameter in response to various stimuli.

Answer: O
 Large veins, such as the vena cavae and jugular veins, function to transport blood from the body back to the heart. They have thinner walls than arteries and less smooth muscle in their tunica media.

Answer: H
 Venules are small blood vessels that collect blood from the capillary bed and transport it to larger veins. They have thinner walls than arterioles and a larger lumen diameter.

Answer: P
 Arterioles are small blood vessels that regulate blood flow to capillary beds by changing their diameter in response to various stimuli. They are considered resistance vessels.

Answer: K
 Capacitance vessels, such as the venous sinuses in the liver and spleen, can hold larger amounts of blood due to their distensible walls. They function to maintain blood volume and regulate venous return to the heart.

Answer: N
 Metarterioles are small blood vessels that connect arterioles to capillaries. They allow for the shunting of blood flow from arterioles directly into venules without passing through a capillary bed, a phenomenon known as arteriovenous anastomosis.

Match Each Vascular Structure to Its Function or Characteristic