Question 1

Neutrophils and lymphocytes are the primary phagocytic cells in the body's defense mechanism.

Accepted Answer

Neutrophils and macrophages (monocytes)are the primary phagocytic cells.

Question 2

The thymus generally enlarges after puberty to provide additional protection for the adolescent.

Accepted Answer

The thymus generally regresses after puberty.

Question 3

A secondary response relies on memory cells.

Accepted Answer

Memory cells are responsible for the secondary response in the immune system. They are activated if the same pathogen enters the body again, allowing for a quicker and more effective response.

Question 4

The thoracic duct drains lymph from all of the following regions EXCEPT the
A) right leg
B) left arm
C) left leg
D) right arm
E) left side of the face

Accepted Answer

The thoracic duct drains lymph from the left side of the body and the lower right side, including the left arm, left leg, and left side of the face, but not from the right arm. The right arm's lymph drains into the right lymphatic duct.

Question 5

The wall of a lymph capillary is composed of overlapping cells that form one-way valves.These cells are
A) simple squamous epithelium
B) stratified squamous epithelium
C) simple cuboidal epithelium
D) loose connective tissue
E) smooth muscle cells

Accepted Answer

The cells that compose the wall of a lymph capillary are simple squamous epithelium cells that overlap and form one-way valves. These cells are thin and flattened, allowing for easy diffusion of lymph fluid and small molecules.

Question 6

Immunoglobulins are antibodies.

Accepted Answer

Immunoglobulins, also known as antibodies, are proteins produced by the immune system in response to the presence of specific antigens (foreign substances) in the body.

Question 7

A molecule,generally a protein,that triggers an immune response is an antigen.

Accepted Answer

This statement is true. An antigen can be any molecule, such as a protein or carbohydrate, that is recognized by the immune system and triggers an immune response. Antigens can be found on the surface of pathogens, cancer cells, and even on cells from other individuals in a transplant situation. Vaccines work by introducing antigens to the immune system in a safe manner, so that the immune system can learn to recognize and respond to these antigens if they are encountered in the future.

Question 8

Lymph capillaries in the small intestine that absorb fats are called
A) lacteals
B) chyle
C) cisterna chili
D) lymphatic trunks

Accepted Answer

Lymph capillaries in the small intestine that absorb fats are called lacteals. Chyle refers to the milky white lymph fluid that is composed of fatty acids and absorbed from the intestines into the lacteals. Cisterna chyli is a lymphatic sac located at the lower end of the thoracic duct where it empties into the venous system. Lymphatic trunks are larger lymphatic vessels that are formed by the convergence of smaller lymphatic vessels.

Question 9

Active immunity last longer than passive immunity.

Accepted Answer

Active immunity is acquired through the body's own immune response, such as from exposure to a pathogen or through vaccination. The immune response produces memory cells that can quickly recognize and fight off the pathogen if it is encountered again in the future. This means that active immunity can last a long time, even for a lifetime in some cases. Passive immunity, on the other hand, is acquired through the transfer of antibodies from another source, such as a mother's breast milk or an injection of pre-formed antibodies. This type of immunity does not produce memory cells and therefore does not last as long as active immunity.

Question 10

The smallest lymphatic vessels are the lymphatic
A) ducts
B) capillaries
C) trunks
D) nodes

Accepted Answer

The smallest lymphatic vessels are the lymphatic capillaries. Lymphatic ducts refer to the major lymphatic vessels that empty into the bloodstream, lymphatic trunks refer to the larger vessels that are formed by the convergence of smaller vessels, and lymph nodes are small, bean-shaped structures that filter lymphatic fluid.

Question 11

All of the following are functions of the lymphatic system EXCEPT to
A) return excess interstitial fluid to venous blood
B) facilitate the absorption of fats and fat-soluble vitamins
C) increase the osmotic pressure of the blood
D) defend the body against invading microorganisms and disease

Accepted Answer

The lymphatic system does not increase the osmotic pressure of the blood. Its main functions are to return excess interstitial fluid to venous blood, facilitate the absorption of fats and fat-soluble vitamins, and defend the body against invading microorganisms and disease.

Question 12

The spleen filters lymph in addition to serving as a reservoir for blood.

Accepted Answer

It filters blood,lymph is filtered by lymph nodes.

Question 13

Most lymphatic vessels drain into the
A) thoracic duct
B) right lymphatic duct
C) inferior vena cava
D) pulmonary veins
E) right subclavian vein

Accepted Answer

Most lymphatic vessels drain into the thoracic duct, which is the largest lymphatic vessel in the body. It drains lymph from the lower limbs, abdomen, left chest, left arm, and left side of the head, neck and thorax, and empties into the left subclavian vein. The right lymphatic duct drains lymph from the right side of the head, neck and thorax, and empties into the right subclavian vein. However, it only receives lymph from the upper right side of the body, while the thoracic duct receives lymph from the rest of the body. The inferior vena cava and pulmonary veins do not receive lymphatic drainage.

Question 14

Vaccines are used to provide passive artificial immunity.

Accepted Answer

Vaccines provide active artificial immunity and antisera provide passive artificial immunity.

Question 15

There are generally more afferent vessels associated with a lymph node than efferent vessels.

Accepted Answer

This slows the flow of lymph to allow time for cleansing.

Question 16

Lymph enters a lymph capillary by
A) diffusion through the wall of the capillary
B) osmosis through the wall of the capillary
C) pressure from the accumulation of fluid that forces the fluid between the cells that make up the wall
D) pressure from the contraction of the heart

Accepted Answer

Lymph capillaries are designed to be highly permeable to allow for the entry of interstitial fluid, which contains lymphocytes and other immune cells. The pressure from the accumulation of fluid within the interstitial space forces the fluid between the cells of the lymph vessel wall and into the lumen of the capillary. Once inside, the lymph is propelled further through the lymphatic system by the contraction of smooth muscles in the vessel walls and skeletal muscle contractions.

Question 17

All of the following are components of the lymphatic system EXCEPT
A) tonsils
B) thymus
C) spleen
D) liver

Accepted Answer

The liver is not a component of the lymphatic system. The lymphatic system includes the lymph nodes, lymphatic vessels, spleen, tonsils, thymus, and bone marrow, which work together to remove waste, toxins, and other harmful substances from the body and help fight infections.

Question 18

One of the functions of the lymphatic system is to pick up excess interstitial fluid and return it to venous blood.This process
A) occurs only when blood capillaries are not functioning properly
B) helps to maintain normal blood volume and prevent edema
C) occurs only in the lower extremities where blood tends to pool and plasma leaks out of the capillaries
D) keeps a normal electrolyte balance in the interstitial fluid
E) allows blood to be cleansed by phagocytic cells in the lymphatic system

Accepted Answer

The function of the lymphatic system to pick up excess interstitial fluid and return it to venous blood helps to maintain normal blood volume and prevent edema. This is important in preventing the accumulation of excess fluid in tissues, which can lead to swelling and tissue damage. The lymphatic system plays a crucial role in regulating fluid balance in the body.

Question 19

B-cells are responsible for cell-mediated immunity.

Accepted Answer

T-cells are responsible for cell-mediated immunity.

Question 20

Lymph is
A) excess plasma
B) interstitial fluid that has entered a lymph capillary
C) blood that has escaped through a broken vessel
D) a suspension of formed elements and water

Accepted Answer

Lymph is interstitial fluid that has entered a lymph capillary.

Quiz 14: Lymphatic System and Body Defense

Neutrophils and lymphocytes are the primary phagocytic cells in the body's defense mechanism.

The thymus generally enlarges after puberty to provide additional protection for the adolescent.

A secondary response relies on memory cells.

The thoracic duct drains lymph from all of the following regions EXCEPT the

The wall of a lymph capillary is composed of overlapping cells that form one-way valves.These cells are

Immunoglobulins are antibodies.

A molecule,generally a protein,that triggers an immune response is an antigen.

Lymph capillaries in the small intestine that absorb fats are called

Active immunity last longer than passive immunity.

The smallest lymphatic vessels are the lymphatic

All of the following are functions of the lymphatic system EXCEPT to

The spleen filters lymph in addition to serving as a reservoir for blood.

Most lymphatic vessels drain into the

Vaccines are used to provide passive artificial immunity.

There are generally more afferent vessels associated with a lymph node than efferent vessels.

Lymph enters a lymph capillary by

All of the following are components of the lymphatic system EXCEPT

One of the functions of the lymphatic system is to pick up excess interstitial fluid and return it to venous blood.This process

B-cells are responsible for cell-mediated immunity.

Lymph is