Chapter 20

Capillaries are never more than 100 micrometers away. What is the main component of interstitial fluid?

What steps can you take to reduce your risk of a heart attack or stroke?

The endothelium is found in the ___________. a. tunica intima b. tunica media c. tunica externa d. lumen

Nervi vasorum control ___________. a. vasoconstriction b. vasodilation c. capillary permeability d. both vasoconstriction and vasodilation

Closer to the heart, arteries would be expected to have a higher percentage of ___________. a. endothelium b. smooth muscle fibers c. elastic fibers d. collagenous fibers

Which of the following best describes veins? a. thick walled, small lumens, low pressure, lack valves b. thin walled, large lumens, low pressure, have valves c. thin walled, small lumens, high pressure, have valves d. thick walled, large lumens, high pressure, lack valves

An especially leaky type of capillary found in the liver and certain other tissues is called a ___________. a. capillary bed b. fenestrated capillary c. sinusoid capillary d. \(\quad\) metarteriole

In a blood pressure measurement of \(110 / 70\), the number 70 is the ___________. a. systolic pressure b. diastolic pressure c. pulse pressure d. mean arterial pressure

A healthy elastic artery ___________. a. is compliant b. reduces blood flow C. is a resistance artery d. has a thin wall and irregular lumen

Which of the following statements is true? a. The longer the vessel, the lower the resistance and the greater the flow. b. As blood volume decreases, blood pressure and blood flow also decrease. c. Increased viscosity increases blood flow. d. All of the above are true.

Slight vasodilation in an arteriole prompts a ___________. a. slight increase in resistance b. huge increase in resistance c. slight decrease in resistance d. huge decrease in resistance

Venoconstriction increases which of the following? a. blood pressure within the vein b. blood flow within the vein C. return of blood to the heart d. all of the above

Hydrostatic pressure is ___________. a. greater than colloid osmotic pressure at the venous end of the capillary bed b. the pressure exerted by fluid in an enclosed space C. about zero at the midpoint of a capillary bed d. all of the above

Net filtration pressure is calculated by ___________. a. adding the capillary hydrostatic pressure to the interstitial fluid hydrostatic pressure b. subtracting the fluid drained by the lymphatic vessels from the total fluid in the interstitial fluid c. adding the blood colloid osmotic pressure to the capillary hydrostatic pressure d. subtracting the blood colloid osmotic pressure from the capillary hydrostatic pressure

Clusters of neurons in the medulla oblongata that regulate blood pressure are known collectively as ___________. a. baroreceptors b. angioreceptors c. the cardiomotor mechanism d. the cardiovascular center

In the renin-angiotensin-aldosterone mechanism, ___________. a. decreased blood pressure prompts the release of renin from the liver b. aldosterone prompts increased urine output c. aldosterone prompts the kidneys to reabsorb sodium d. all of the above

In the myogenic response, ___________. a. muscle contraction promotes venous return to the heart b. ventricular contraction strength is decreased c. vascular smooth muscle responds to stretch d. endothelins dilate muscular arteries

A form of circulatory shock common in young children with severe diarrhea or vomiting is ___________. a. hypovolemic shock b. anaphylactic shock C. obstructive shock d. hemorrhagic shock

The coronary arteries branch off of the ___________. a. aortic valve b. ascending aorta C. aortic arch d. thoracic aorta

Which of the following statements is true? a. The left and right common carotid arteries both branch off of the brachiocephalic trunk. b. The brachial artery is the distal branch of the axillary artery. c. The radial and ulnar arteries join to form the palmar arch. d. All of the above are true.

Arteries serving the stomach, pancreas, and liver all branch from the ___________. a. Superior mesenteric artery b. inferior mesenteric artery c. celiac trunk d. splenic artery

The right and left brachiocephalic veins ___________. a. drain blood from the right and left internal jugular veins b. drain blood from the right and left subclavian veins c. drain into the superior vena cava d. all of the above are true

The hepatic portal system delivers blood from the digestive organs to the ___________. a. liver b. hypothalamus C. Spleen d. left atrium

Blood islands are ___________. a. clusters of blood-filtering cells in the placenta b. masses of pluripotent stem cells scattered throughout the fetal bone marrow C. vascular tubes that give rise to the embryonic tubular heart d. masses of developing blood vessels and formed elements scattered throughout the embryonic disc

Which of the following statements is true? a. Two umbilical veins carry oxygen-depleted blood from the fetal circulation to the placenta. b. One umbilical vein carries oxygen-rich blood from the placenta to the fetal heart. C. Two umbilical arteries carry oxygen-depleted blood to the fetal lungs. d. None of the above are true.

The ductus venosus is a shunt that allows ___________. a. fetal blood to flow from the right atrium to the left atrium b. fetal blood to flow from the right ventricle to the left ventricle C. most freshly oxygenated blood to flow into the fetal heart d. most oxygen-depleted fetal blood to flow directly into the fetal pulmonary trunk

Arterioles are often referred to as resistance vessels. Why?

Cocaine use causes vasoconstriction. Is this likely to increase or decrease blood pressure, and why?

A blood vessel with a few smooth muscle fibers and connective tissue, and only a very thin tunica externa conducts blood toward the heart. What type of vessel is this?

An obese patient comes to the clinic complaining of swollen feet and ankles, fatigue, shortness of breath, and often feeling "spaced out." She is a cashier in a grocery store, a job that requires her to stand all day. Outside of work, she engages in no physical activity. She confesses that, because of her weight, she finds even walking uncomfortable. Explain how the skeletal muscle pump might play a role in this patient's signs and symptoms.

A patient arrives at the emergency department with dangerously low blood pressure. The patient's blood colloid osmotic pressure is normal. How would you expect this situation to affect the patient's net filtration pressure?

True or false? The plasma proteins suspended in blood cross the capillary cell membrane and enter the tissue fluid via facilitated diffusion. Explain your thinking.

Identify the ventricle of the heart that pumps oxygendepleted blood and the arteries of the body that carry oxygen-depleted blood.

What organs do the gonadal veins drain?

What arteries play the leading roles in supplying blood to the brain?

All tissues, including malignant tumors, need a blood supply. Explain why drugs called angiogenesis inhibitors would be used in cancer treatment.

Explain the location and importance of the ductus arteriosus in fetal circulation.