Ch 20 Blood Vessels

All arteries carry oxygen-rich blood, whereas veins carry oxygen-poor blood. True False

Which of the following statements about arteries is false? Arteries have a smaller lumen than veins of similar size. Arterial walls are thicker than venous walls. Arteries have more elastin than veins. Arteries carry oxygenated blood to the heart.

Layer of blood vessels innervated by sympathetic vasomotor fibers. vasa vasorum tunica intima tunica externa tunica media subendothelial layer

The elastic arteries are the largest arteries near the heart. True False

Muscular arteries regulate blood flow to organs and groups of organs. True False

Arterioles and venules have a vasa vasorum to provide nutrients to their outer walls, whereas the inner walls receive nutrients from blood in the lumen. True False

Systemic blood pressure is regulated by adjusting the diameter of arterioles. True False

By definition, veins are the only vessels that lead from capillaries. vessels that always carry nutrient-poor blood. vessels that carry oxygen-poor blood. vessels that carry blood toward the heart.

Which of the following statements about arterioles is false? They regulate the flow of blood to capillary beds through contraction and relaxation of the tunica media. They redirect blood flow in a sympathetic response to skeletal muscle. They have the largest content of smooth muscle in their tunica media. They can lead into metarterioles.

A blood vessel that ranges from 0.3 mm to about 1 cm in diameter and has a large tunica media relative to the size of the lumen is an arteriole. a muscular artery. an elastic artery. a capillary.

Functionally, there are no valves in arteries (as opposed to in veins) because valves would tear apart from the high arterial pressure. the blood pressure in arteries is high enough that there is no backflow of blood. valves direct blood only toward the heart and arterial blood passes away from the heart. arteries get more atherosclerosis, so valves would cause lethal blood clotting.

Which layer of blood vessels contains smooth muscle tissue? tunica adventitia tunica intima tunica media tunica externa

What is distinctive about the tunica media of arteries when compared to the tunica media of veins? The tunica media is thicker in arteries than in veins. The tunica media of arteries anchors the vessel to surrounding structures. The tunica media of arteries contains elastin and collagen. The tunica media of arteries is primarily comprised of flat endothelial cells.

The external elastic lamina of muscular arteries forms __________ and its function is __________. thick tunica media / regulation of the amount of blood flowing to an organ outer layer of the tunica media / dampening pulsatile pressure produced by the heartbeat outer layer of the tunica intima / contraction and relaxation of blood vessel wall to regulate the amount of blood sent downstream small arteries and capillaries within large muscular arteries / supplying blood to the larger arteries and veins

The diameter of arterioles is regulated by __________. local factors (chemicals) in peripheral tissues signaling smooth muscle cells to either contract or relax the skeletal muscle pump valves inside the arterioles precapillary sphincters the parasympathetic division of the ANS adjusting diameter to regulate systemic blood pressure

Elastic arteries __________. have the smallest diameter of all arteries, but still possess all three tunics are found only in the cerebral arterial circle (Circle of Willis) have the greatest diameter of all arteries and includes the aorta. range from 1 cm to 0.3 mm in diameter and supply groups of organs, individual organs, and parts of organs do not exist in humans

Varicose veins are twisted, swollen superficial venous blood vessels, and usually occur in the lower limbs. What are the main causes of varicose veins? Varicose veins can result from obesity and pregnancy, because the increased weight constricts the leg draining valves. They may be caused by genetic factors, such as incompetent venous valves. Varicose veins may be caused by increased build-up of blood, as a result of gravitational pressure and nonmoving legs (standing for long periods of time), as might occur in people who work as store clerks, hairdressers, and dentists, for example. All of the listed responses are correct

In metabolically active tissues, blood is present in metarterioles, and precapillary sphincters are constricted. True False

The diameter of a typical capillary is similar to that of a venule. an erythrocyte. a fat cell. a sinusoid.

What prevents the backflow of blood in veins? thick smooth muscle and elastic layers increased blood pressure the narrowed lumen valves

Fenestrated capillaries occur in most of the organs of the body. have pores in their walls. are located in the central nervous system. permit the movement of very few molecules.

In a capillary bed, relaxation of the precapillary sphincters causes more blood to flow through the true capillaries. into the thoroughfare channels. into the arterioles. through the metarterioles.

Blood pressure is highest in the elastic arteries. arterioles. veins. capillaries.

Microvasculature that provides nourishment to the outer walls of the aorta. tunica externa vasa vasorum subendothelial layer tunica media tunica intima

Vessels of the small intestines, renal glomerulus, and synovial membranes that allow passage of fluid and solutes through "windows" in the endothelium. metarterioles sinusoids fenestrated capillaries continuous capillaries none of the above

Precapillary sphincters allow blood to leave this structure and enter true capillaries. continuous capillaries metarterioles fenestrated capillaries sinusoids none of the above

Structure that regulates blood flow into true capillaries. fenestrations metarteriole thoroughfare channel precapillary sphincter sinusoids

A "coming together" of alternate pathways of blood vessels. metarterioles vasa vasorum converging veins vascular anastomosis thoroughfare channel

Continuous capillaries __________. are the least common type of capillary occur where there are rapid rates of exchange of small molecules between blood and peripheral tissues have "pores" that span the endothelial cells are found in most organs of the body, such as skeletal muscles, skin, and the CNS have wide passages for large molecules, proteins, and cells

What is the function of valves in veins? They compensate for the larger lumens of veins compared to arteries of similar size. They help propel blood with great velocity. They counteract low venous pressure, and prevent backflow of blood away from the heart. They are the reason that a relatively higher amount of blood resides in veins, compared to arteries.

Site-specific functions of capillaries include __________. receiving digested nutrients in the small intestine exchange of oxygen and carbon dioxide in the lungs transporting hormones from endocrine glands removal of nitrogenous wastes from the kidneys All of the listed functions are site-specific functions of capillaries.

Where do arterial anastomoses occur in the body? in the kidneys and around the brain around joints and the heart in the central artery of the retina and the kidneys in the spleen and near the epiphyses of long bones

The internal iliac arteries supply blood both to the pelvic organs and to the lower limbs. True False

The pulse of the posterior tibial artery is palpated behind the knee. True False

Which of the following is not a branch of the celiac trunk? splenic artery sigmoidal artery left gastric artery common hepatic artery

The main arteries of the sole of the foot-the medial and lateral plantar arteries-arise behind the ankle from which artery? saphenous dorsalis pedis fibular posterior tibial

Which artery arises from the inferior part of the abdominal aorta and supplies the distal half of the large intestine? gonadal artery superior phrenic artery median sacral artery inferior mesenteric artery

The correct proximal to distal sequence of the three vessels branching from the aortic arch is left common carotid, left subclavian, brachiocephalic. left subclavian, left common carotid, brachiocephalic. brachiocephalic, left common carotid, left subclavian. brachiocephalic, left subclavian, left common carotid.

The abdominal aorta divides at its distal end into which arteries? the femoral arteries the internal iliac arteries the external iliac arteries the common iliac arterie

Which branch (or branches) of the abdominal aorta supplies the stomach? suprarenal arteries inferior phrenic arteries celiac trunk superior mesenteric artery

If a physician cannot feel a pulse in the popliteal fossa, the ________ artery is most likely narrowed by atherosclerosis. dorsalis pedis fibular femoral greater saphenous

The dorsalis pedis artery is located by placing a finger behind the medial malleolus. finding the head of the fibula and palpating inferior to its neck. palpating between the first and second metatarsal. placing the fingers behind the knee.

The pulse of the facial artery is palpated anterior to the sternocleidomastoid. anterior to the auricle of the ear near the temple. anterior to the masseter muscle at the inferior margin of the mandible. in the anterior triangle of the neck.

The saphenous vein is not paired with an artery with the same name. True False

The circulatory route that runs from the digestive tract to the liver is called pulmonary circulation. hepatic portal circulation. cerebral circulation. coronary circulation.

The right gonadal vein drains into the lumbar vein. internal iliac vein. inferior vena cava. renal vein.

The right suprarenal and gonadal veins drain into the inferior vena cava, whereas the left suprarenal and gonadal veins drain into the superior vena cava. hepatic portal system. other side of the inferior vena cava. left renal vein.

Most systemic venous blood is both oxygen-poor and nutrient-poor. However, systemic venous blood that is not oxygen-poor and is nutrient-rich occurs in the pulmonary veins. the hepatic portal vein. the renal vein. superficial veins of the limbs.

Which vessel is most commonly used to bypass a damaged coronary artery in coronary bypass surgery? femoral artery great saphenous vein azygos vein internal carotid artery

The hepatic portal system has two distinct capillary beds separated by a portal vein. What are the functions of these two capillary beds? The first provides oxygen to the liver, and the second picks up nutrients from the liver. The first nourishes the digestive tube, and the second picks up nutrients from the digestive tube. The first picks up digested nutrients, and the second delivers these nutrients to liver cells. The first picks up toxins from the liver, and the second delivers them to the digestive tube for detoxification.

An aneurysm is a sac-like widening or outpocketing of an artery. a buildup of fatty deposits on an arterial wall. a rupture in an artery. a stroke.

The foramen ovale in the heart normally closes in the 2-month fetus. shortly after birth. in the 7-month fetus. never.v

What vessel in the fetus connects the pulmonary trunk to the aortic arch so that most of the blood bypasses the immature lungs? ductus venosus foramen ovale umbilical vein ductus arteriosus

Blood passing through the fetal ductus arteriosus bypasses the right atrium and ventricle. right ventricle, pulmonary trunk, and lungs. pulmonary trunk and lungs. lungs, left atrium, and ventricle.

Paired fetal umbilical veins carry blood from the fetus to the placenta, whereas the unpaired umbilical artery returns blood from the placenta to the fetus. True False

three layers of blood vessels

tunica intima

tunica media

contraction of tunica media

relaxation of tunica media

tunica externa

arteries

capillaries

veins

elastic arteries

muscular (distributing) arteries

arterioles

function of capillaries in lungs

function of capillaries in the small intestine

function of capillaries in the endocrine glands

function of capillaries in the kidneys

how do RBCs pass through capillaries?

capillary beds

precapillary sphincters

types of capillary permeability

blood pressure is lower in

small veins are called

thickest layer in veins

mechanisms to counteract low venous pressure

vascular anastomoses

vasa vasorum

pulmonary circulation

aorta

ascending aorta

aortic arch

branches of aortic arch

multivein bundles

superior vena cava

inferior vena cava

veins of the head and neck

veins of upper limbs

veins of thorax

hepatic portal system

veins of pelvis and lower limbs