Anatomy chapter 22 & 24

Lymph nodes A. filter lymph. B. contain a network of collagen fibers. C. serve as auxiliary exchange surfaces for respiratory gases. D. filter blood.

filter lymph.

Which bears a close structural relationship with the fossa ovalis? A. Papillary muscles B. Trabeculae carneae C. Conus arteriosus D. Foramen ovale

foramen ovale

"Booster" shots are required following certain vaccinations because the memory B-lymphocytes produced in response to the initial vaccination don't survive indefinitely. T/F?

true

About seventy percent of the ventricle filling is achieved passively without the contraction of the atria. T/F?

true

All cardiac veins eventually drain into the coronary sinus for return of the blood from the myocardium to the right atrium. T/F?

true

All of the heart's sulci house blood vessels that supply the myocardium. T/F?

true

It is during weeks 5-8 that the single heart tube of the embryo becomes partitioned into four chambers and the main vessels that leave and enter the heart form. t/F

true

It is the contraction of the atria during atrial systole that completes the filling of the ventricles while the ventricles are in diastole. T/F?

true

Like the right atrium, the left atrium has pectinate muscles along its anterior wall. T/F?

true

No matter the cause, hypertrophy of the heart causes it to work less efficiently. T/F?

true

Normal passage of blood from the atria to the ventricles only happens if the atrioventricular valves are open. T/F?

true

One of the functions of the lymphatic system is to transport fat. T/F?

true

One reason that necessitates the relatively early development of the heart is that the embryo has become too large to receive adequate nutrient supply by diffusion alone. T/F?

true

Parasympathetic innervation decreases the heart rate, but generally tends to have no effect on the force of contractions. T/F?

true

The embryonic heart actually begins working before its development is complete. T/F?

true

The gap junctions of intercalated discs provide a low-resistance pathway across the membranes of adjoining cardiac muscle fibers. T/F?

true

The germinal center of a lymphatic nodule contains proliferating B-lymphocytes and macrophages. T/F

true

The left ventricle has a wall that is typically three times thicker than the right ventricular wall. T/F?

true

The right and left coronary arteries are the only branches of the ascending aorta. T/F?

true

The thymus gland begins to atrophy after puberty. T/F

true

The walls of lymphatic capillaries are only one cell thick. T/F?

true

Though the autonomic innervation by autonomic centers in the brainstem cannot initiate a heartbeat, it can increase or decrease the heart rate. T/F?

true

Which prenatal structure forms the ascending aorta and pulmonary trunk? A. Truncus arteriosus B. Sinus venosus C. Primitive atrium D. Primitive ventricle

Truncus arteriosus

Regions of MALT called Peyer patches are found in the A. urinary bladder. B. stomach. C. vagina. D. small intestine.

small intestine.

During a cardiac cycle, how many of the four chambers contract at any one time? A. 1 B. 2 C. 4 D. Highly variable, depending on the heart beat rate

2

How many half-moon shaped, pocketlike cusps are found in each semilunar valve? A. 1 B. 2 C. 3 D. 4

3

Which values are reasonable for a healthy, 80 kilogram resting adult? A. 5.25 liters of blood pumped per ventricle per minute; 108,000 beats per day B. 4.25 liters of blood pumped per ventricle per minute; 60,000 beats per day C. 6.75 liters of blood pumped per ventricle per minute; 20,000 beats per day D. 7.25 liters of blood pumped per ventricle per minute; 76,000 beats per day

5.25 liters of blood pumped per ventricle per minute; 108,000 beats per day

Of the four "normal" heart sounds, the initial "lubb" sound is heard when the A. AV valves close. B. semilunar valves close. C. AV valves open. D. semilunar valves open.

AV valves close.

The anteromedial border of the spleen A. is concave. B. contains the hilum. C. is also called the visceral surface. D. is where the splenic artery enters. E. All of the choices are correct.

All of the choices are correct.

Which does not drain into the coronary sinus? A. Great cardiac vein B. Small cardiac vein C. Anterior interventricular vein D. Middle cardiac vein

Anterior interventricular vein

Which are not among the primary lymph sacs that form during the sixth week of development? A. Jugular lymph sacs B. Anterior lymph sacs C. Retroperitoneal lymph sac D. Cisterna chyli

Anterior lymph sacs

Which structure marks the end of the left ventricle and the entrance to the aorta? A. Pulmonary semilunar valve B. Left atrioventricular valve C. Right atrioventricular valve D. Aortic semilunar valve

Aortic semilunar valve

Which valve prevents the backflow of blood into the left ventricle when the ventricles relax? A. Left atrioventricular valve B. Aortic semilunar valve C. Right atrioventricular valve D. Pulmonary semilunar valve

Aortic semilunar valve

Which is not a type of lymphatic cell? A. Macrophage B. Nurse cell C. Dendritic cell D. Astrocyte

Astrocyte

Lymphoid stem cells mature into A. B-lymphocytes. B. T-lymphocytes. C. B-lymphocytes and T-lymphocytes. D. B-lymphocytes, T-lymphocytes, and NK cells.

B-lymphocytes, T-lymphocytes, and NK cells.

Of the lymphatic trunks, which ones drain lymph from deep thoracic structures? A. Jugular trunks B. Subclavian trunks C. Bronchomediastinal trunks D. Intestinal trunks

Bronchomediastinal trunks

Parasympathetic innervation of the heart occurs via A. CN IV. B. CN VI. C. CN VIII. D. CN X.

CN X.

Helper T-lymphocytes are also known as A. cytotoxic T-lymphocytes. B. CD8+ cells. C. CD4+ cells. D. T8 cells.

CD4+ cells.

Lymph nodes may be found individually, or clustered in specific regions of the body. Which cluster of lymph nodes receives lymph from the head and neck? A. Inguinal lymph nodes B. Cervical lymph nodes C. Thoracic lymph nodes D. Axillary lymph nodes

Cervical lymph nodes

Which is not correct regarding lymph nodes? A. They are covered by a connective tissue capsule. B. They contain a network of lymphatic sinuses. C. Each node has an outer cortex and inner medulla. D. Connective tissue bands called tendineae divide nodes.

Connective tissue bands called tendineae divide nodes.

Which action causes the closure of the right atrioventricular valve? A. Contraction of the right atrium B. Contraction of the left atrium C. Contraction of the right ventricle D. Contraction of the left ventricle

Contraction of the right ventricle

Which is not a function of the spleen? A. Serves as blood reservoir B. Filters blood C. Filters lymph D. Recycles aged erythrocytes

Filters lymph

When is the thymus gland most active? A. From ages 25-45 years B. From childhood to puberty C. From puberty to adulthood D. From ages 45-65 years

From childhood to puberty

Which cell type is targeted by the human immunodeficiency virus (HIV)? A. Cytotoxic T-lymphocyte B. Memory B-lymphocyte C. Helper T-lymphocyte D. Natural killer cell

Helper T-lymphocyte

Which of the lymphatic trunks drain into the cisterna chyli? A. Intestinal trunks B. Lumbar trunks C. Intestinal trunks and lumbar trunks D. Subclavian trunks and jugular trunks

Intestinal trunks and lumbar trunks

Which is not correct regarding the spleen? A. It has an outer cortex and inner medulla. B. It is divided into sections by capsular extensions called trabeculae. C. Its white pulp consists of lymphatic cells. D. It stores erythrocytes.

It has an outer cortex and inner medulla.

Which analogy fits the human heart? A. It is like a single pump. B. It is like a double pump, each working side by side with the other. C. It is like four pumps working in alternating cycles. D. It is like a double pump, each working at its own rate determined by the needs of the body served.

It is like a double pump, each working side by side with the other.

Which is not correct regarding the white pulp of the spleen? A. Its cells include T-lymphocytes, B-lymphocytes, and macrophages. B. Its cells are arranged in clusters that are circular in shape. C. Its cells can initiate the immune response. D. It serves as a blood reservoir.

It serves as a blood reservoir.

Which is not correct regarding the thymus gland? A. It is a bilobed organ located in the mediastinum. B. It is fully encapsulated by connective tissue. C. Each thymic lobe is subdivided into lobules. D. Its thymic corpuscles are the site of T-lymphocyte maturation.

Its thymic corpuscles are the site of T-lymphocyte maturation.

With respect to the lymphatic system, what do the letters in the acronym MALT stand for? A. Membrane-adhering lymphatic T-cells B. Mucosa-associated lymphatic tissue C. Multiple-antigen lymphocyte target D. Multiple-antibody lymphocyte test

Mucosa-associated lymphatic tissue

Which type of lymphocyte responds to multiple antigens? A. Memory B-lymphocyte B. Memory T-lymphocyte C. Natural killer cell D. Plasma cell

Natural killer cell

Which is not a function of the lymphatic system? A. Transports dietary lipids B. Returns excess interstitial fluid to the bloodstream C. Houses and develops lymphocytes D. Generates immune responses E. No exceptions; all choices are functions of the lymphatic system.

No exceptions; all choices are functions of the lymphatic system.

Which area does not contain MALT? A. Urinary tract B. Respiratory tract C. Genital tract D. Gastrointestinal tract E. None of the choices is correct.

None of the choices is correct.

Which lymphatic structures form from the pharyngeal pouches? A. Palatine tonsils B. Lingual tonsils C. Thymus gland D. Palatine tonsils and thymus gland

Palatine tonsils and thymus gland

Which are not tonsils? A. Adenoids B. Palatine tonsils C. Pharyngeal tonsils D. Palatoglossal tonsils

Palatoglossal tonsils

Which is not a type of T-lymphocyte? A. Helper T-lymphocyte B. Cytotoxic T-lymphocyte C. Memory T-lymphocyte D. Plasma T-lymphocyte

Plasma T-lymphocyte

Which type of lymphocyte produces and secretes antibodies? A. Memory B-lymphocyte B. Memory T-lymphocyte C. Natural killer cell D. Plasma cell

Plasma cell

Which correctly describes the heart's apex? A. Projects slightly anteroinferiorly toward the left side of the body B. Projects slightly anteroinferiorly toward the right side of the body C. Projects slightly posteroinferiorly toward the left side of the body D. Projects slightly posteroinferiorly toward the right side of the body

Projects slightly anteroinferiorly toward the left side of the body

Which of the cardiovascular system's circuits has deoxygenated blood in its arteries? A. Pulmonary circuit B. Systemic circuit C. Coronary circuit

Pulmonary circuit

Which carries oxygenated blood from the lungs to the heart? A. Pulmonary arteries B. Pulmonary veins C. Pulmonary trunk D. Inferior vena cava

Pulmonary veins

What is the function of a lymphocyte's coreceptors? A. Recognize particular antigens B. Produce antibodies C. Initiate mitosis to generate memory lymphocytes D. Monitor pH of interstitial fluids

Recognize particular antigens

Where do B-lymphocytes develop immunocompetence? A. Spleen B. Red bone marrow C. Lymph nodes D. Thymus gland

Red bone marrow

A variety of lymphatic cells are involved in the immune response. Which is not part of the process? A. Production of antibodies B. Direct attack and destruction of foreign or abnormal agents C. Replication of antigens D. Formation of memory cells

Replication of antigens

Which pair is located more anteriorly in a heart in normal position? A. Left atrium and left ventricle B. Left atrium and right ventricle C. Right atrium and left atrium D. Right atrium and right ventricle

Right atrium and left atrium

Which heart chambers pump deoxygenated blood? A. Left atrium and right atrium B. Left ventricle and right ventricle C. Right atrium and right ventricle D. Left atrium and left ventricle

Right atrium and right ventricle

Which is not drained by the right lymphatic duct? A. Right side of abdomen B. Right side of thorax C. Right side of head and neck D. Right shoulder

Right side of abdomen

What part of the cardiac conduction system is located in the posterior wall of the right atrium, adjacent to the entrance of the superior vena cava? A. AV bundle B. Bundle branches C. Purkinje fibers D. SA node

SA node

What is the function of nurse cells in the thymus gland? A. Nourish developing T-lymphocytes B. Transport mature T-lymphocytes to the bloodstream C. Secrete thymic hormones D. Destroy moribund T-lymphocytes

Secrete thymic hormones

This figure shows the lymphatic system. What structure does number 8 indicate? A. Lymphatic nodule B. Thymus gland C. Cisterna chyli D. Spleen

Spleen

Which lymphatic organ contains red pulp and white pulp? A. Thymus gland and lymph nodes B. Spleen and lymph nodes C. Lymph nodes D. Spleen

Spleen

The left atrium and left ventricle are part of which circuit of the cardiovascular system? A. Pulmonary circuit B. Systemic circuit

Systemic circuit

Which circuit of the cardiovascular system is responsible for sending blood to the kidneys, stomach, and pelvic regions? A. Pulmonary circuit B. Systemic circuit C. Coronoary circuit

Systemic circuit

Sympathetic innervation of the heart arises from the ________ segments of the spinal cord. A. T1T5 B. T3T8 C. T5T10 D. T6T11

T1T5

Which may predispose one to inadequate coronary blood flow? A. Bradycardia B. Hypertension C. Angina pectoris D. Tachycardia

Tachycardia

When women with breast cancer undergo surgery to remove the tumor or the entire breast, the axillary lymph nodes are often removed as well. Why? A. In removing the breast, the blood supply to the nodes is removed and they will inevitably cease to function. B. The axillary lymph nodes receive lymph from the breast and may contain cancer cells. C. The nerves that supply the axillary lymph nodes are often cut during the breast surgery. D. It is impossible to remove the breast without physically damaging the lymph nodes.

The axillary lymph nodes receive lymph from the breast and may contain cancer cells.

Which is not correct regarding lymphatic nodules? A. The central portion of a lymphatic nodule is called the germinal center. B. The tonsils are clusters of lymphatic nodules. C. The cells and matrix of a lymphatic nodule are enclosed within a thick connective tissue capsule. D. B-lymphocytes are located at the center of a nodule, whereas T-lymphocytes lie outside the center.

The cells and matrix of a lymphatic nodule are enclosed within a thick connective tissue capsule.

Which is not correct regarding lymph nodes? A. They contain strands of lymphatic cells supported by medullary cords. B. They are drained by afferent lymphatic vessels. C. They contain phagocytic cells. D. They filter lymph.

They are drained by afferent lymphatic vessels.

What is the function of dendritic cells within lymph nodes? A. They initiate replication of macrophages. B. They conduct signals between activated T-lymphocytes to accelerate the immune response. C. They collect antigens and present them to T-lymphocytes. D. They secrete lymphatic hormones to stimulate adjacent lymph nodes.

They collect antigens and present them to T-lymphocytes.

Where do T-lymphocytes develop immunocompetence? A. Spleen B. Red bone marrow C. Lymph nodes D. Thymus gland

Thymus gland

The cardiac cycle is A. when the ventricles are contracting. B. when the atria are relaxed. C. when the atria are contracting. D. all the events involved with a single heart beat.

all the events involved with a single heart beat.

The great cardiac vein runs alongside the A. anterior interventricular artery. B. posterior interventricular artery. C. right marginal artery. D. circumflex artery.

anterior interventricular artery.

Pectinate muscles are found on the A. anterior wall of the right atrium. B. posterior wall of the right ventricle. C. anterior wall of the right ventricle. D. anterior wall of the right and left atria.

anterior wall of the right and left atria.

It is the _____________ that permits the compression necessary to pump large volumes of blood out of the ventricles. A. negative pressure inside the ventricles B. absence of oxygenated blood in the atria C. arrangement of cardiac muscle in the heart wall D. presence of skeletal muscle tissue in the heart skeleton

arrangement of cardiac muscle in the heart wall

The beginning of the cardiac cycle is when the A. atria fill with blood. B. ventricles fill with blood. C. atria contract. D. two semilunar valves close.

atria contract.

In an EKG, the P wave is generated when the A. ventricles depolarize. B. atria depolarize. C. atria repolarize. D. ventricles repolarize.

atria depolarize.

The papillary muscles attach to the cusps of the atrioventricular valves by means of the A. pectinate muscles. B. trabeculae carneae. C. conus arteriosus. D. chordae tendineae.

chordae tendineae.

The chordae tendineae are made out of A. collagen fibers. B. elastin fibers. C. hyaline cartilage. D. reticulin fibers.

collagen fibers.

Cardiac muscle fibers A. contract as a single unit. B. are only loosely connected by the intercalated discs. C. have a low oxygen need. D. utilize hemoglobin as an energy source.

contract as a single unit.

. The left and right coronary arteries travel within the A. anterior interventricular sulcus. B. posterior interventricular sulcus. C. coronary sulcus. D. interventricular septum.

coronary sulcus.

The atria are separated from the ventricles externally by the A. anterior interventricular sulcus. B. posterior interventricular sulcus. C. sinoventricular sulcus. D. coronary sulcus.

coronary sulcus.

Tonsils have multiple germinal centers and invaginated outer edges called _______ that help trap material. A. crypts B. trabeculae C. sinuses D. clefts

crypts

Which is not correct regarding B-lymphocytes? A. They must be activated by helper T-lymphocytes, which present antigens to them. B. Activated B-lymphocytes transform into plasma cells, memory B-lymphocytes, or NK cells. C. Memory B-lymphocytes may live for months or even years. D. B-lymphocytes produce immunoglobulins.

ctivated B-lymphocytes transform into plasma cells, memory B-lymphocytes, or NK cells.

Once a helper T-lymphocyte recognizes an antigen, it begins the immune response by secreting chemical signals called A. antibodies. B. immunoglobulins. C. memory B-lymphocytes. D. cytokines

cytokines

The primary goal of the immune response is A. destruction or inactivation of pathogens and foreign material. B. maintenance of the proper ionic balance between lymph and blood. C. stimulation of mitotic activity in order to replace cells damaged by infection. D. reduction of the number of circulating memory lymphocytes.

destruction or inactivation of pathogens and foreign material.

During isovolumetric contraction, the atria are in A. systole. B. diastole.

diastole.

B-lymphocytes make up the largest population of lymphocytes in the body, about 70-85% of the total number. T/F?

false

Because of the constant inflow of blood, the atria are thick-walled and located inferiorly in the heart. T/F?

false

During ventricular contraction the semilunar valves close in order to permit the blood to enter the large arterial trunks that carry blood away from the heart. T/F?

false

Helper T-lymphocytes primarily contain the CD8 coreceptor. T/F?

false

In an aging heart, increased flexibility of the heart valves may lead to a heart murmur. T/F?

false

The acronym HIV stands for "human immune virus". T/F

false

The relatively small size of the Purkinje fibers allows for the extremely rapid impulse conduction through the ventricles. T/F?

false

The spleen is essentially a giant lymph node, since it is encapsulated, has trabeculae, and filters lymph to remove antigens. T/F

false

Though some lymphocytes are housed in lymphatic organs, most circulate continuously in the bloodstream. T/F?

false

With increasing age, the lymphatic system becomes unable to transport lymph from body tissues and fat from the gastrointestinal tract. T/F

false

The pharyngeal tonsils are located A. along the posterior margins of the tongue. B. in the posterior wall of the nasopharynx. C. at the base of the palatoglossal arches. D. in the posterolateral region of the oral cavity.

in the posterior wall of the nasopharynx.

The function of helper T-lymphocytes is to A. initiate and oversee the immune response. B. turn off the immune response once it has been activated. C. secrete toxins to kill or disable pathogens. D. trigger cell death by disrupting metabolic activities.

initiate and oversee the immune response.

The foramen ovale is actually an opening in the A. interventricular septum. B. interatrial septum. C. fossa ovalis. D. aorticopulmonary septum.

interatrial septum.

The cell-to-cell contacts of the cardiac muscle fibers are called A. Z discs. B. T-tubules. C. intercalated discs. D. cardiac discs.

intercalated discs.

The composition of lymph is most similar to A. whole blood. B. blood plasma. C. interstitial fluid. D. extracellular fluid.

interstitial fluid.

Lymph A. is found only when there is a pathological condition that allows it to leak from capillaries. B. is excess interstitial fluid. C. is filtered by the spleen. D. is synthesized by the lymphoid organs.

is excess interstitial fluid.

With advancing age, the lymphatic system A. becomes less efficient at absorbing dietary lipids. B. ceases to transport lymph. C. produces an increasing number and variety of B-lymphocytes. D. is less responsive to antigens.

is less responsive to antigens.

Lymphatic capillaries A. cannot be discerned structurally from cardiovascular system capillaries. B. originate as closed-ended tubes associated with blood capillary networks. C. filter lymph. D. concentrate lymph prior to passing it to larger lymphatic vessels.

originate as closed-ended tubes associated with blood capillary networks.

Lymphatic capillaries A. are open at both ends. B. are smaller in diameter than blood capillaries. C. have wide gaps between endothelial cells. D. lack a basement membrane.

lack a basement membrane.

A lymphatic capillary that picks up dietary lipids in the small intestine is called a(n) A. cisterna chyli. B. lacteal. C. afferent lymphatic vessel. D. trabeculum.

lacteal.

The base of the heart is formed primarily by the A. right atrium. B. right ventricle. C. left atrium. D. left ventricle.

left atrium.

The serous fluid within the pericardial cavity works to A. lubricate the membranes of the serous pericardium. B. slow the heart rate. C. equalize the pressure in the great vessels. D. eliminate blood pressure spikes.

lubricate the membranes of the serous pericardium.

The primary lymph sacs eventually develop into the A. lymph nodes. B. spleen. C. spleen and thymus gland. D. thoracic duct and right lymphatic duct.

lymph nodes.

Developmentally, the spleen forms from A. ectoderm. B. mesoderm. C. endoderm. D. aggregations of lymphatic cells.

mesoderm.

The trabeculae carneae in the left ventricle are ____________ in the right ventricle. A. less prominent than B. not present as C. more prominent than D. equally as prominent as

more prominent than

The layer of the heart wall composed of cardiac muscle tissue is the A. pericardium. B. myocardium. C. endocardium. D. pericardial cavity.

myocardium.

For ___________ of the cardiac cycle, all four chambers are in diastole together. A. none B. one-third C. one-quarter D. one-half

one-half

The heart valves A. stabilize and hold the arteries leaving the heart. B. permit the passage of blood in one direction. C. separate the right and left sides of the heart. D. are only used in the fetal heart.

permit the passage of blood in one direction.

As blood is pumped into the arterial trunks past the semilunar valves, it A. pushes against the cusps, forcing the valves open. B. pushes against the cusps, forcing the valves closed. C. fills the cusps, causing them to expand and block the backflow of blood. D. fills the cusps, causing them to expand and open up for the flow of blood.

pushes against the cusps, forcing the valves open.

In an EKG, the T wave denotes A. depolarization of the atria. B. depolarization of the right ventricle. C. repolarization of the ventricles. D. closure of the AV valves.

repolarization of the ventricles.

The thoracic duct collects lymph from all of the following except the A. abdomen. B. left leg. C. right arm. D. right foot.

right arm.

The right border of the heart is supplied by the A. circumflex artery. B. posterior interventricular artery. C. anterior interventricular artery. D. right marginal artery.

right marginal artery.

Within the red pulp of the spleen are enlarged capillaries called _________, which have a discontinuous basal lamina that allows blood cells to enter and exit easily. A. splenic cords B. trabecular vessels C. splenic vessels D. splenic sinusoids

splenic sinusoids

Thymic hormones A. are secreted in response to stimulation by activating hormones from the pituitary gland. B. stimulate T-lymphocyte maturation and differentiation. C. are produced by the cortical lymphocytes. D. are stored in thymic corpuscles prior to release.

stimulate T-lymphocyte maturation and differentiation.

The thoracic duct and the right lymphatic duct empty lymph into the A. superior vena cava. B. subclavian veins. C. inferior vena cava. D. azygos vein

subclavian veins.

The function of the coronary sinus is to A. connect the top and bottom halves of the heart. B. guide the aorta out of the heart. C. guide the inferior vena cava into the right atrium. D. take blood from the coronary circulation to the right atrium.

take blood from the coronary circulation to the right atrium.

T-lymphocytes in the thymus gland do not participate in the immune response and are protected from antigens by A. the blood-thymus barrier. B. thymic macrophages. C. the low pH of the thymus gland. D. circulating B-lymphocytes.

the blood-thymus barrier.

During ventricular diastole A. only the AV valves open. B. only the AV valves close. C. only the semilunar valves close. D. the semilunar valves close and the AV valves open.

the semilunar valves close and the AV valves open.

During ventricular systole A. only the AV valves open. B. only the AV valves close. C. only the semilunar valves close. D. the semilunar valves open and the AV valves close.

the semilunar valves open and the AV valves close

The arteries and veins that leave and enter the heart are called the great vessels because A. they are associated with the heart directly. B. they carry the most highly oxygenated blood. C. they are longer than any other blood vessels in the body. D. they have relatively large diameters.

they have relatively large diameters.

Development of the heart commences in the _______ week. A. first B. third C. fifth D. eighth

third

Excess interstitial fluid enters lymphatic capillaries A. by diffusion. B. through gated channels in response to changes in ion balance. C. by pinocytosis. D. through one way flaps

through one way flaps

Lymphatic capillaries originate in the A. central nervous system. B. red bone marrow. C. yellow bone marrow. D. tissue spaces between cells.

tissue spaces between cells.

The internal wall surface of each ventricle displays large, smooth, irregular muscular ridges called A. conus arteriosus. B. atrioventricular opening. C. trabeculae carneae. D. chordae tendineae

trabeculae carneae.

Typically, there are __________ papillary muscles that project from the wall of the left ventricle and attach to the chordae tendineae that support the left AV valve. A. three B. two C. a highly variable number of D. six

two

Because lymphatic vessels have three tunics (intima, media, and externa) and valves, they structurally resemble A. veins. B. arterioles. C. venules. D. arteries

veins.

The inferior chambers of the heart are the A. atria. B. auricles. C. ventricles. D. sulci.

ventricles.

One example of cardiac arrhythmia is _________, in which a rapid, repetitious movement of the ventricular muscle replaces normal contractions. A. atrial fibrillation B. atrial flutter C. ventricular fibrillation D. premature ventricular contraction

ventricular fibrillation

The epicardium is another name for the A. visceral layer of the serous pericardium. B. parietal layer of the serous pericardium. C. pericardium. D. myocardium.

visceral layer of the serous pericardium.