Final Exam Biology (Chapters 17,18,19)

The following are structural components of the conducting system of the heart. 1. Purkinje fibers 2. AV bundle 3. AV node 4. SA node 5. bundle branches The sequence in which excitation would move through this system is which of the following?

4, 3, 2, 5, 1

Define cardiac cycle. (Module 18.9A)

Cardiac cycle is the period between the start of one heartbeat and the beginning of the next.

Why can cardiac tamponade be a life-threatening condition? (Module 18.2C)

Cardiac tamponade can be life-threatening because accumulating fluid in the pericardial cavity restricts heart movement.

________ transport(s) oxygen and CO2 in the RBCs.

Hemoglobin molecules

How does a treatment with anti-Rh antibodies (RhoGAM) prevent hemolytic disease of the newborn (HDN)?

It destroys fetal RBCs that enter the maternal circulation.

Why is it beneficial for capillary pressure to be very low? (Module 19.5C)

It is beneficial for capillary pressure to be low to allow time for diffusion between the blood and the surrounding interstitial fluid.

Abnormally slow depolarization of the ventricles would most change the shape of the ________ in an ECG tracing.

QRS complex

Depolarization of the ventricles is represented on an electrocardiogram by the

QRS complex.

Materials can move across capillary walls by

Reabsorption, filtration, and diffusion all are correct

Why is RhoGAM administered to pregnant Rh women ? (Module 17.8B)

RhoGAM contains anti-Rh antibodies, which circulate in the mothers' bloodstream to destroy any fetal RBCs there, thereby preventing the mother from making antibodies against the developing fetus's red blood cells.

________ is to contraction as ________ is to relaxation.

Systole; diastole

Why is the left ventricle more muscular than the right ventricle? (Module 18.6A)

The left ventricle must generate enough force to propel blood through the systemic circuit, whereas the right ventricle must generate only enough force to propel blood the short distance from the heart to the lungs in the pulmonary circuit.

Which of the following statements is false concerning the movement of fluid between capillaries and interstitial space?

The net filtration pressure is usually zero.

Which blood type(s) can be safely transfused into a person with type O- blood? (Module 17.7C)

They can receive only O- blood.

________ refers to all the factors that resist blood flow in the entire circulatory system.

Total peripheral resistance

Why are valves located in veins but not in arteries? (Module 19.4A)

Valves are located in veins to prevent blood from flowing backward because venous pressure is too low to keep the blood moving back toward the heart.

Why is ventricular fibrillation fatal? (Module 18.13C)

Ventricular fibrillation is fatal because the ventricles quiver and do not pump blood to the systemic circulation.

When a person who lives at sea level vacations in the Rocky Mountains, you would expect

a rise in hematocrit, the release of erythropoietin, a drop in oxygen levels. All answers are correct.

In which of the following would the blood flow be highest?

a vessel 1.0 cm in diameter and 2 meters long

In which of the following would the resistance be greater?

a vessel 10 microns in diameter

List the five general classes of blood vessels. (Module 19.2A)

arteries, arterioles, capillaries, venules, and veins

White blood cells that release histamine at the site of an injury are

basophils

The ________ valve prevents backward flow into the left atrium.

bicuspid

Erythropoiesis is stimulated when

both oxygen levels in the blood decrease and blood flow to the kidney declines.

________ are the only blood vessels whose walls are thin enough to permit blood-tissue exchange.

capillaries

Metabolites exchange by diffusion with the tissues and the cells in which of the following locations?

capillary

Red blood cell production is regulated by the hormone ________ which is mostly produced in the ________.

erythropoietin; kidneys

Capillaries that contain pores that penetrate the endothelial cells are called _______.

fenestrated capillaries

Rouleaux refers to the ability of RBCs to

form stacks

Pacemaker cells in the SA node

generate action potentials that spread to the myocardium.

The yellow color that is visible in the eyes and skin in jaundice results from all of the following except

hematuria

The waste product bilirubin is produced from

heme molecules lacking iron

More than 95 percent of the protein in a red blood cell is

hemoglobin

Plasma proteins essential in body defense are the

immunoglobulins

Which specific plasma proteins would you expect to be elevated during an infection? (Module 17.2C)

immunoglobulins

The atrioventricular valves permit blood flow

in one direction only

David suffers from a prolapsed mitral valve. This condition would cause

increased effort by the left ventricle and regurgitation.

Each of the following changes will result in increased blood flow to a tissue except

increased hematocrit.

In large arteries, the thick layer of elastic fibers is called the________.

internal elastic membrane

Blood returning to the heart from the pulmonary circuit first enters the

left atrium

Name the four chambers of the heart. (Module 18.1C)

left atrium, left ventricle, right atrium, right ventricle

Sinusoids can be found in the _______.

liver

All of the following are components of the cardiovascular system except

lymph vessels

The entire space between the pleural cavities containing only the heart, great vessels, thymus, trachea and esophagus is called the

mediastinum.

________ are large phagocytic white cells that spend most of their time outside the blood as fixed and free phagocytic cells.

monocytes

The muscle layer of the heart is the

myocardium

The most numerous white blood cells in peripheral circulation are the

neutrophils

The average lifespan of a red blood cell is

4 months

The combination of plasma and formed elements is called

whole blood

Intercalated discs serve to transfer all of the following from cell to cell except

z-lines

The cavity that contains only the heart is the

pericardial cavity.

Blood flow through a capillary is controlled by the ______.

precapillary sphincters

A person's blood type is determined largely by the

presence of specific glycoproteins on the cell membrane.

As blood travels from arteries to veins,

pressure drops.

Contractions of the papillary muscles

prevent the atrioventricular valves from reversing into the atria.

Which of the following is not a function of blood?

produce hormones

Damage to the semilunar valve on the right side of the heart would affect blood flow to which vessel? (Module 18.6B)

pulmonary trunk

Compared to the right ventricle, the left ventricle has all the following characteristics except that it

pumps a greater volume

All the circulating red blood cells originate in the

red bone marrow

During the T wave of the electrocardiogram, the ventricles are electrically ________ and functionally ________.

repolarizing; relaxing

Blood returning to the heart from the systemic circuit first enters the

right atrium

These vessels hold the largest percentage of the blood supply.

systemic venous system

A faster-than-normal heart rate is called

tachycardia.

The process of white blood cell production and maturation goes on in all of the following except

the kidney

Sensitization during hemolytic disease of the newborn refers to

the mother's immune system producing antibodies against the fetus' RBCs.

Total peripheral resistance is related to all of the following except

the osmolarity of interstitial fluids.

If the connection between the SA node and AV node becomes blocked,

the ventricles will beat more slowly.

If the blood types of a donor and recipient are compatible, then

there is no reaction between antibodies and antigens.

The muscular layer of a blood vessel is the________.

tunica media

The process of decrease in any vessel diameter that occurs due to smooth muscle contraction is called?

vasoconstriction

Venoconstriction reduces the diameter of which vessel?

vein

Each of the following is a characteristic of whole blood except

viscosity about the same as water

A person with Type A blood has

antigen A on the RBCs and anti-B antibodies in the plasma.

The ________ valve opens when left ventricular pressure exceeds aortic blood pressure.

aortic

The first heart sound is heard when the

AV valves close.

Define autorhythmicity. (Module 18.12A)

Autorhythmicity is the ability of the heart to contract without neural or hormonal stimulation.

Define edema. (Module 19.8B)

Edema is an abnormal accumulation of interstitial fluid in peripheral tissues.

At what sties in the body are fenestrated capillaries located? (Module 19.3B)

Fenestrated capillaries are located in endocrine glands, the choroid plexus of the brain, absorptive areas of the intestine, and filtration areas of the kidneys.

The most abundant proteins in blood plasma are

albumins

The term used to describe fluid collecting in the pericardial cavity that restricts the movement of the heart is known as

cardiac tamponade.

The cusps (leaflets) of atrioventricular valves attach directly to

chordae tendineae

The first heart sound ("lubb") is associated with

closing of the mitral valve.

________ involves a cascade of reactions leading to the conversion of fibrinogen to fibrin.

coagulation

Capillaries that have a complete lining are called ________.

continuous capillaries

Platelets are

cytoplasmic fragments of large cells

Which of these descriptions best matches the term lymphocytes?

defend against specific pathogens or toxins

The P wave of the electrocardiogram is a signal from

depolarization of the atria.

The process of fibrinolysis

dissolves clots

If blood pressure doubled, the blood flow through a vessel would be

doubled