The blood vessels that play the most important role in regulating blood pressure and blood flow to a tissue are the:

(a) Arteries

(b) Arterioles

(c) Veins

(d) Venules

(e) Capillaries

The baroreceptors in the carotid sinus and aortic arch are sensitive to

a. a decrease in CO₂

b. changes in arterial pressure

c. a decrease in O₂

d. all of these

The myocardium receives its blood supply directly from the:

a. Aorta

b. Coronary arteries

c. Coronary sinus

d. Pulmonary arteries

The two arteries formed by the division of the brachiocephalic trunk are the:

(a) Aorta and internal carotid

(b) Axillary and brachial

(c) External and internal carotid

(d) Common carotid and subclavian

The unpaired arteries supplying blood to the visceral organs include:

(a) The adrenal, renal, and lumbar arteries

(b) The iliac, gonadal, and femoral arteries

(c) The celiac and superior and inferior mesenteric arteries

(d) All of these

The paired arteries supplying blood to the body wall and other structures outside the abdominopelvic cavity include the:

a) Left gastric, hepatic, splenic, and phrenic arteries

(b) Adrenal, colic, lumbar, and gonadal arteries

(c) Iliac, femoral, and lumbar arteries

(d) Celiac, left gastric, and superior and inferior mesenteric arteries

Distinguish between elastic arteries, muscular arteries, and arterioles relative to location, histology, and functional adaptations.