Chapter 21: Blood Vessels and Circulation

The layer of vascular tissue that consists of an endothelial lining and an underlying layer of connective tissue dominated by elastic fibers is the

tunica interna

Smooth muscle fibers in arteries and veins are found in the

tunica media

One of the major characteristics of the arteries supplying peripheral tissues is that they are

muscular

The only blood vessels whose walls permit exchange between the blood and the surrounding interstitial fluids are

capillaries

One of the primary characteristics of continuous capillaries is that they

prevent the loss of blood cells and plasma proteins

The unidirectional flow of blood in venules and medium-sized veins is maintained by

the presence of valves

The specialized arteries that are able to tolerate the pressure shock produced each time ventricular systole occurs and blood leaves the heart are

elastic arteries

Of the following blood vessels, the greatest drop in blood pressure occurs in the

arterioles

If the systolic pressure is 120mm Hg and the diastolic pressure is 90 mm Hg, the mean arterial pressure (MAP) is

100 mm Hg

The distinctive sounds of Korotkoff heard when taking the blood pressure are produced by

turbulences as blood flows past the constricted portion of the artery

The phenomenon that helps maintain blood flow along the arterial network while the left ventricle is in diastole is

elastic rebound

The most important factor in vascular resistance is

friction between blood and the vessel walls

Two factors that assist the low venous pressures in propelling blood toward the heart are

muscular compression of peripheral veins and the respiratory pump

From the following selections, choose the answer that correctly identifies all the factors that would increase blood pressure

increasing CO, increasing SV, increasing VR, increasing PR, increasing BV

The two major factors affecting blood flow rates are

pressure and resistance

For circulation to occur, the circulatory pressure must be sufficient to overcome the

total peripheral resistance

Atrial natriuretic peptide reduces blood volume and pressure by

blocking release of ADH, stimulating peripheral vasodilation, increased water loss by the kidneys

The circulatory-regulatory mechanisms that can assist in short-term and long-term adjustments are

endocrine responses

The regulatory mechnism that cause immediate, localized homeostatic adjustments is

autoregulation

The central regulation of cardiac output primarily involves the activities of the

autonomic nervous system

An increase in cardiac output normally occurs during

widespread sympathetic stimulation

Stimulation of the vasomotor center in the medulla causes ___________________ and inhibition of the vasomotor center causes _______________

vasoconstriction; vasodilation

Hormonal regulation by vasopressin, epinephrine, angiotensin II, and norepinephrine results in

increasing peripheral vasoconstriction

The three primary interrelated changes that occur as exercise begins are

increasing vasodilation, increasing venous return, increasing cardiac output

The only area of the body where the blood supply is unaffected while exercising at maximum levels is the

brain

The four large blood vessels, two from each lung, that empty into the left atrium, completely the pulmonary circuit, are the

pulmonary veins

The blood vessels that provide blood to capillary networks that surround the alveoli in the lungs are

left and right pulmonary veins

Other than near the heart, the peripheral distributions of arteries and veins on the left and right sides are

generally identical on both sides

As the external iliac artery leaves the body trunk and enters the lower limb, it becomes the

femoral artery

The link between adjacent arteries or veins that reduces the impact of a temporary or permanent occlusion of a single blood vessel is

an anastomosis

The three elastic arteries that originate along the aortic arch and deliver blood to the head, neck, shoulders, and arms are the

brachiocephalic, L. common carotid, left subclavian

The large blood vessel that collects most of the venous blood from organs below the diaphragm is the

inferior vena cava

The three blood vessels that provide blood to all of the digestive organs in the abdominopelvic cavity are the

celiac artery and the superior and inferior mesenteric arteries

The diaphragm divides the descending aorta into

superior thoracic aorta and inferior abdominal aorta

The three unpaired arteries originating from the abodominal aorta are the

L. gastric, splenic, and common hepatic arteries

Except for the cardiac veins, all the body's systemic veins drain into either the

superior or inferior vena cava

Blood from the tissues and organs of the head, neck, chest, shoulders, and upper limbs is delivered to the

superior vena cava

Blood from the lower limbs, the pelvis, and the lower abdomen is delivered to the

external iliac veins

Blood leaving the capillaries supplied by the celiac, superior, and inferior mesenteric arteries flows into the

hepatic portal system

The nutritional and respiratory needs of a fetus are provided by

diffusion across the placenta

In early fetal life, the foramen ovale allows blood to flow freely from the

right atrium to the left atrium

In the adult, the ductus arteriosus persists as a fibrous cord called the

lifamentum arteriosum

A few seconds after birth, rising O2 levels stimulate the constriction of the ductus arteriosus, isolating the

pulmonary and aortic trunks

The primary effect of a decrease in the hematocrit of elderly individuals is

a lowering of the oxygen-carrying capacity of the blood

In the heart, age-related progressive atherosclerosis causes

restricted coronary circulation

The systems responsible for modifying heart rate and regulating blood pressure are the

nervous and endocrine systems

The branches of the popliteal artery are

anterior and posterior tibial arteries

Intraveling from the heart to the peripheral capillaries, blood passes through

elastic arteries, muscular arteries, and arterioles

In general terms, blood flow (F) is directly proportional to

pressure

The goal of cardiovascular regulation is

maintenance of adequate blood flow through the peripheral tissues and organs

Along the length of a typical capillary, blood pressure gradually falls from about

30 to 18 mm Hg

In which of the following organs would you find fenestrated capillaries

filtration areas of the kidneys, absorptive areas of the intestine, endocrine glands

The average pressure in arteries is approximately

100 mm Hg

The effective pressure in the venous system is roughly

16 mm Hg

Net hydrostatic pressure forces water ______ a capillary; net osmotic pressure forces water _____ a capillary

out of; into

Of the following selections, the condition that would have the greatest peripheral resistance is

doubling the diameter of a blood vessel

The relationship F - P/R means

flow is directly proportional to the pressure gradient and inversely proportional to resistance

To increase blood flow to an adjacent capillary, the local controls that operate are

decreasing O2, increasing CO2, decreasing pH

The adrenergic fiber innervating arterioles are ______ fibers that release ______ and cause ______

sympathetic; norepinephrine; vasoconstriction

Two arteries formed by the bifurcation of the brachiocephalic artery are the

common carotid, subclavian

The artery that serves the posterior thigh is the

deep femoral

A major difference between the arterial and venous systems is that

there is dual venous drainage in the limbs

The large vein that drains the thorax is the

azygos vein

The veins that drain the head, neck, and upper extremities are the

brachiocephalics

The veins that drain venous blood from the legs and the pelvis are

common iliacs

The vein that drains the knee region of the body is the

popliteal

The large artery that serves the brain is the

internal carotid

The artery that links the subclavian and brachial arteries is the

axillary

The three arterial branches of the celiac trunk are the

L. gastric, splenic, and hepatic

The artery that supplies most of the small intestine and the first half of the large intestine is the

superior mesenteric

The artery that supplies the pelvic organs is the

internal iliac artery