Bio 122 - Unit 5

transplanted tissue may be tolerated if:

***All of the above*** -the tissue involves few cells or has a limited blood supply -lymphatic tissue is destroyed by irradiation or chemicals -the histocompatibility antigens of donor and recipient are very similar.

Inflammation produces localized

***All of the answer are correct*** -Swelling -Redness -Heat -Pain

lymphocyte production involves

***All of the answers are correct*** -Bone Marrow -Thymus Tissue -Peripheral lymphoid tissues

the role of antigen-presenting cells in immunity is to

***All of the answers are correct*** -activate T cells -display antigen fragments -process antigens

The binding of an antigen to an antibody can result in

***All of the answers are correct*** -neutralization of the antigen -agglutination or precipitation -Complement activation and opsonization

Which of the following statements regarding lymph is false?

***Lacteals are prominent lymphatic vessels in the cardiopulmonary system. a) Lymph derives from interstitial fluid. b) Lymphatic vessels have valves to direct fluid flow. c) Lymphatic capillaries have larger diameters than that of blood capillaries. d) Lacteals are prominent lymphatic vessels in the cardiopulmonary system. e) Lymphatic capillaries have little or no basement membrane.

MHC proteins

***all of the above are correct*** -are present on the surface of our bodies' cells -can be recognized by T cells -are histocompatibility antigens

Nonspecific defenses include

***all of the following are correct*** -phagocytic cells -physical barriers -inflammation -interferons

Examples of physical barriers against pathogens include

***e) All of the answers are correct.a) sebaceous glands. b) mucus. c) epithelia. d) epidermal layers.

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

**right breast** a) left breast. b) right breast. c) left arm and shoulder. d) left side of the neck.

Penicillin allergy is termed a hypersensitivity reaction. The statement that is true of most people allergic to penicillin is that these individuals:

Will respond strongly the second time they are given penicillin.

Immune surveillance against cancer is:

a function of cell-mediated immunity

What is perforin?

a protein produced by NK cells

Cytotoxic T cells attack target cells by doing what?

activating genes that trigger apoptosis

The process by which antibodies bind to the antigen on the surface of cells, forming large immune complexes, is called

agglutination

Inappropriate or excessive immune responses to antigens are

allergies

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

an antibody attached to an antigen

A condition in which the body attacks itself as if it were a microbe is:

an auto-immune disease

A condition in which, for example, the body forms antibodies against its own red blood cells is called:

an auto-immune disease

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

antigen

Antibodies:

are specific to the antigen that stimulated their production

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

b and t cells

Which lymphocytes are responsible for antibody-mediated immunity?

b cells

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

chemotaxis of phagocytes

Of the following, which directly defends against intracellular viruses by attacking infected cells?

cytotoxic T lymphocytes

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

Which of the body's defenses is mainly directed against viruses?

interferon

Which nonspecific defense mechanism increases the resistance of cells to viral infection and slows the spread of disease?

interferons

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

involution

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

is running a fever

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

it is delayed by the memory cell stage

The white pulp of the spleen is populated by

lymphocytes

Someone who is vaccinated against diphtheria will respond almost immediately if later exposed to the disease. What cells are directly responsible for rapidly recognizing the pathogen and responding?

memory B cells

Which cell is responsible for antibody production?

plasma cell

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

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

A crime scene investigator found that a biological fluid sample contains a large amount of IgA-type antibody. This fluid is probably

tears

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.

Lymph draining from your right shoulder flows into

the right lymphatic duct

The lymphatic system is composed of all of the following except

the venae cavae

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

thoracic duct

the thymus produces several complementary hormones called

thymosins

T cell means ________ and B cell means________.

thymus-dependent; bone marrow-derived

The large lymphoid nodules located in the walls of the pharynx are called

tonsils

The site on an antibody that is specifically tailored to fit a specific antigen is called the

variable segment

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

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

a(n) ____________________ will develop when the immune response mistakenly targets normal body cells and tissues

Autoimmune disorders

the medullary sinus of a lymph node contains __________ lymphocytes and plasma cells

B

The t-cells of the immune system are responsible for the production of antibodies. True/False

False

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

Helper T Cells

The human immunodeficiency virus (HIV) which causes the disease known as AIDS, selectively infects _____________ cells.

Helper T Cells

B cells are primarily activated by the activities of

Helper T cells

What is the effect of histamine release?

Histamine increases local inflammation, increasing blood flow to the area.

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

IgA

Antigen-detecting cells are found chiefly in the:

Lymph Nodes

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

Memory

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

Memory

The cells that perform immunological surveillance are the ________ cells.

NK

of the following types of cells, the type that bind to cells bearing foreign antigens and kill them directly (No prior exposure to the antigen is required) is called:

Natural Killer (NK) cells

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

Neutrophils invade the surrounding areas, releasing chemotactic substances

A patient is given an injection of immunoglobulin after an exposure to hepatitis. This is known as:

Passive Humoral Immunity

the cells responsible for producing antibody molecules are __________ cells

Plasma

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

Produce a fever

Which of the following is a response of cell-mediated immunity?

Secretion of chemotactic factors by T cells

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

Sensitization

B and T cells are similar in that they both

Stem from precursors in the bone marrow

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

T

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

T Cell

Adaptive immunity is the result of the actions of

T and B cells

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

T cells

Lymphoid organs differ from lymphoid tissues in what way?

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

Recognition of self and non-self is a function related to the:

Thymus gland

A(n) __________ exists when the immune system does not respond to a particular antigen.

Tolerance

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

Tonsils

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

Viruses

Fever is the maintenance of body temperature greater than

98.6 Degrees F

In opsonization

A pathogen is coated by proteins to facilitate its destruction by neutrophils and macrophages.

During an inflammatory response:

Capillary permeability is increased

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

Cytotoxic T (Killer T cells)

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

chemotaxis

T cells are important in:

Detecting cancer cells

the B cell system is most effective against

bacteria

Lymphatic vessels commonly occur in association with

blood vessels

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

Infection with HIV virus occurs through

direct contact with an infected persons body fluid

autoantibodies are

directed against the body's own antigens.

Before specific defenses are activated, most antigens must

either infect cells or be processed by a phagocyte

An overreaction of the body's immune system can occur in some instances after a second exposure to a foreign antigen. Mild instances might include hay fever, a more serious reaction may produce anaphylactic shock. This is called:

hypersensitivity

Suppressor T cells act to

inhibit T and B cell activities.

Various types of macrophages are derived from

monocytes

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

naturally acquired passive

Antibodies may bind to superficial sites of the bacteria or other toxins, making the toxin incapable of attaching itself to a cell. This mechanism is known as

neutralization

Which type of blood cell is migratory and phagocytic, acting as a ready body defense against infection, and comprises 50% to 70% of all leukocytes?

neutrophil

The most immediate reaction launched against a bacterial infection involves:

neutrophils (phagocytes)

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