Anatomy and physiology chapter 20 the lymphatic system and immunity

What is perforin?

a protein produced by NK cells

All of the following are true of the thymus gland except that it

activates B cells

Cytotoxic T cells attack target cells by doing what?

activating genes that trigger apoptosis

Identify the structure labeled "3."

afferent lymphatic

The classic pathway of complement activation begins when the complement protein binds to

an antibody attached to an antigen

Nonspecific defenses would not include

antibodies

A substance that provokes an immune response is called a(n)

antigen

Compared to blood capillaries, lymph capillaries exhibit all of the following except that they

are smaller in diameter

Histamine increases blood flow and vascular permeability. This would account for all of the following changes that occur during inflammation except

chemotaxis of phagocytes

The thoracic duct originates from an expanded chamber called the

cisterna chyli

Each of the following is a physical barrier to infection except

complement

Lymphocytes that destroy foreign cells or virus- infected cells are ________ cells.

cytotoxic T

The effects of activating the complement system include all of the following except

inhibition of the immune response

Immunity that is genetically determined and present at birth is called ________ immunity.

innate

Characteristics of specific defenses include all of the following except

intrinsic

After puberty, the thymus gradually shrinks and becomes more fibrous, in a process called

involution

A sample of John's blood shows a high level of pyrogens. This would indicate that John

is running a fever

The white pulp of the spleen is populated by

lymphocytes

Class II MHC molecules are found only on which of the following?

lymphocytes and antigen-presenting cells

________ are connective tissues dominated by lymphocytes.

lymphoid tissues

An inflammatory response is triggered when

mast cells release histamine and heparin

cells enable the immune system to respond quickly and robustly if the same antigen is encountered a second time.

memory

The first line of cellular defense against pathogens are the

phagocytes

The role of antigen- presenting cells in immunity is to do all of the following except

phagocytosis

The cells responsible for producing antibody molecules are ________ cells.

plasma

In response to tissue damage and infection, circulating proteins called pyrogens

produce a fever

Lymph nodes do all of the following except

remove excess nutrients from the lymph

Lymphocytes

respond to antigens.

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

right breast

B cells prepare for activation by presenting an antigen bound to Class II MHC proteins in a process called

sensitization

The lobules of the thymus are divided by partitions called

septa

Defense of the body against a particular pathogen is provided by

specific immunity

The largest single collection of lymphoid tissue in the adult body is located in the

spleen

Leslie has a bad sore throat, and the lymph glands in her neck are swollen. This would indicate that

the affected lymph glands contain an increased number of lymphocytes

The merging of ________ forms the right lymphatic duct.

the right jugular, right subclavian, and right bronchomediastinal trunks

All of the following are true of lymphocytes except that

they are granulocytes.

Most of the lymph returns to the venous circulation by way of the

thoracic duct

The thymus produces several complementary hormones called

thymosins

Stem cells that will form T cells develop in the

thymus

T is to ________ as B is to ________.

thymus-dependent; bone marrow-derived

are large lymphoid nodules that are located in the walls of the pharynx.

tonsils

Identify the structures labeled "4."

trabeculae

The lymphatic system is composed of all of the following except

venae cavae

Interferons are released by some macrophages and lymphocytes, but also by cells carrying what pathogen?

viruses

All of the following are true of the secondary response to antigen exposure except that it

weakens quickly because memory B cells only survive for a year or two.

Areas of the spleen that contain large aggregations of lymphocytes are known as

white pulp

The body's nonspecific defenses include all of the following except

B and T cells

Identify the dominant cell type in the area labeled "2."

B cells

T cells release cytokines to stimulate the activation of

B cells

The cells responsible for antibody- mediated immunity are the ________ cells.

B cells

B cells are primarily activated by the activities of

Helper T cells

Immunoglobulins that are primarily found in glandular secretions such as mucus, saliva, and tears are

IgA

Immunoglobulins that are found on the surface of B cells and may activate antibody production are

IgD

Immunoglobulins that attach to and sensitize mast cells and basophils are

IgE

Immunoglobulins that are most abundant and are responsible for resistance against many viruses, bacteria, and bacterial toxins are

IgG

Immunoglobulins, formed of five subunits, which are the first antibodies to be produced in response to infection are

IgM

Which of the following statements regarding lymph is false?

Lacteals are prominent lymphatic vessels in the respiratory system.

The cells that perform immunological surveillance are the ________ cells.

NK

________ are clusters of lymphoid nodules deep to the epithelial lining of the small intestine.

Peyer patches

Regulatory T cells act to

Supress antigens

The cells directly responsible for cell- mediated immunity are the ________ cells.

T

Adaptive immunity is the result of the actions of

T and B cells

If the thymus shrank and stopped functioning properly, we would expect to see an immediate decrease in the number of

T cells

The cell that dominates the deep cortical region of a lymph node is the ________ cell.

T helper

Which of these statements about lymph flow in a node is false?

The afferent lymphatics enters at the hilum.

Lymphocyte production does not occur in

The liver

Lymph draining from your right shoulder flows into

The right lymphatic duct

Lymphoid organs differ from lymphoid tissues in what way?

They are surrounded by a fibrous capsule and lymphoid tissues are not.

exists when the immune system does not respond to a particular antigen.

Tolerance

Identify the area where dividing lymphocytes are found.

WRONG 2 outer cortex

Before specific defenses are activated, most antigens must

WRONG either infect cells or be processed by a phagocyte.

The medullary sinus of a lymph node contains ________ lymphocytes and plasma cells

WRONG helper T

The attraction or repulsion of certain cells to chemicals in their environment is called

chemotaxis

Lymph nodes range in diameter from

1 mm to 25 mm

When an antigen is bound to a Class II MHC protein, it can activate a(n) ________ cell.

CD4 T

________ cells provide cell- mediated immunity.

CD8 T

Lymphatic vessels are located in almost all portions of the body except the

CNS

Which of the following concerning Class I MHC proteins is false?

bind complement

Examples of physical barriers against pathogens include all of the following except

blood

Lymphatic vessels commonly occur in association with

blood vessels

In passive immunity, the

body receives antibodies produced by other humans or by an animal.

Lymphocytes are produced and stored in all of the following except

brain

Inflammation produces all of the localized effects except

decreased blood flow

The primary function of the lymphatic system is

defending the body against both environmental hazards and internal threats.

Helper T cells do all of the following except

destroy target cells using perforins

The movement of phagocytes through the capillary wall is called

diapedesis

Identify the structure labeled "1."

efferent lymphatic

Fever is the maintenance of body temperature higher than

either 37.2°C or 99°F.

The lymphocytes are most important in

fighting infection

Which class of leukocytes is particularly abundant in the red pulp of the spleen?

free and fixed macrophages

Identify the region labeled "5."

germinal center

The various classes of immunoglobulins are differentiated on the basis of their

heavy-chain constant segments.

Cells that help regulate the antibody- mediated immune response are ________ cells.

helper T

Various types of macrophages are derived from

monocytes

Plasma contains ________ proteins that form the complement system.

more than 30

Immunity that results from exposure to an antigen in the environment is called ________ immunity.

naturally acquired active

Immunity that results from antibodies that pass the placenta from mother to fetus is called ________ immunity.

naturally acquired passive

During a primary response to antigen exposure, all of the following occur except

neutrophils invade the surrounding areas, releasing chemotactic substances.

The process by which the surface of a microorganism is covered with antibodies and complement, rendering it more likely to be phagocytized, is called

opsonization

In an experimental situation, a rabbit is exposed to a viral antigen to which it makes antibodies. These antibodies are then purified and injected into a human with the same viral disease. This is an example of

passive immunity