Chapter 21: The Immune System (A&PII)

meningitis

Dangerous infection of the outer lining of the brain

CALT

The Cutaneous Associated Lymphatic Tissue exists to protect the body against pathogens that enter through the skin.

which is not a feature of the thymus?

site of B cell maturation

immunological tolerance

Ability to limit the immune response to foreign antigens only.

_____ selection ensures lymphocytes are able to respond to antigen and _____ selection removes those that respond to self antigen

Positive, negative

Lymph nodes play a key role in immunity by ________.

filtering lymphatic fluid

Which of the following are characteristics of a lymph node?

-secondary lymphatic organ

-filled w. T and B lymphocytes

-impt for neutralizing foreign threats

What are the characteristics of the thymus?

It helps to mature lymphocytes.

Foreign threats are filtered from the lymph by ______________.

lymph nodes

Trace the path a foreign object would take from the interstitial space to the vein passing through the lymphatic system.

1. lymph capillary
2. lymph vessel
3. lymph node
4. veins

Which of the following is not a normal physiological function of the lymphatic vessels?

Growth and development of connective tissue cells

Recognition and memory is part of __________.

Adaptive immunity

The immune system __________________.

- is capable of diff. from self to nonself

-possesses memory of prior exposure to foreign threats

What does the spleen do?

It filters blood.

A lymphocyte _______________.

-is prod by the same process that prod erythrocytes

-has small amnt of cytoplasm

Which of the following is the best definition of a cluster-of-differentiation (CD)?

A CD is a protein expressed on the surface of some but not all lymphocytes.

TH cells

aid in maturation of B-lymphocytes

TC cell-fucnction

destruction of virus infected cells

TM cell function

Store memory of prior exposure to antigen

TR cells

termination of the adaptive immune response

What does a plasma B-lymphocyte do?

-It carries the memory of prior exposure to a foreign threat.

-It produces antibodies.

-Aided by TH cells during maturation

-Can last for the lifetime of a person

Which process physically removes a B- or T-lymphocyte that is recognizing a self-antigen from the body?

Apoptosis

The largest (by area) component of the innate immune system is ______________.

mucosal membrane

sebum

mixture of oily substances and fatty acids

lysozyme

an enzyme found in saliva and sweat and tears that destroys the cell walls of certain bacteria

autocrine

affects same cell that secretes it

paracrine

affects neighboring cells

endocrine

secrete through blood stream to far-away cells

What are cytokines?

-They are part of the innate immune response.

-They are an autocrine factor.

endotoxins

large mlcls consisting of lipid and polysaccharides found on outer membrane of gram negative bacteria

chemotactic agents

diffusing chemical agents that draw cells toward a specific area

leukocytosis factors

factors that increase the proliferation of leukocytes

peroxidase (anti bac)

enzyme released by neutrophils that degrades peroxides

superoxide (anti bac)

very reactive form of diatomic oxygen that damages and destroys foreign threats

hypochlorous acid (antic bac)

HClO as weak acid

Neutrophils are drawn toward sites of infection by _____________.

Chemotactic cues released by infected cells

plasminogen

preotease that degrades many blood proteins including clots

majorbasic protein

involved in the fight against parasitic infections

Fas ligand

transmembrane receptor expressed in many cells that when bound to proteins on the surface of NK cells, induces apoptosis

NK cells secrete ____ and ___ to destroy virally infected cells.

perforin, a-defensins

pseudopodia

A cellular extension of amoeboid cells used in moving and feeding; macrophages have this

Macrophages secrete ______________ to lyse infected cells.

perforin

How does T-lymphocyte activation differ from B-lymphocyte activation?

T-lymphocytes interact with antigen-presenting cells.

Which of the following statements best explains the concept of memory within the adaptive immune system?

Increased growth of specific B- or T-lymphocytes after antigen exposure

What is the first step in B-lymphocyte activation?

Binding of antigen to the BcR

Describe the process by which an APC presents an antigen to other cells.

An APC engulfs and digests the foreign protein and then presents peptide fragments on the surface of the MHC complex for other immune cells to detect.

Why do some cells have both MHC I and MHC II proteins expressed on their surface?

Antigen-presenting cells, which express MHC II, also need to establish that they are a self-cell, so they need to also express MHC I on their surface.

Predict what would happen if MHC II was removed from the surface of macrophages.

The macrophage could no longer present antigens to TH-lymphocytes.

Which antibody type activates complement?

IgM, IgG

Why does IgA make up only 15% of serum antibodies even though it is produced at a higher rate each day than any other antibody?

IgA are found in surface secretions on mucosal membranes, protecting against foreign threats without triggering inflammation.

What is an antigen?

It is recognized by the adaptive immune system.

What type of immunity is her son gaining by these vaccinations?

Adaptive artificial immunity

Which of the following is an example of passive artificial adaptive immunity?

Injection of blood factors collected from patients who successfully fought off a hepatitis infection into a nurse accidently stuck with a needle

How does acute inflammation differ from chronic inflammation?

Acute inflammation lasts for a short period of time, chronic inflammation lasts for a long time.

Inflammation is triggered by ______________.

infection

Interferons carry out which of the following in innate immunity?

Direct attacks on virally infected cells

Complement _________________.

-Acts as an opsonin to increase phagocytosis of foreign threats by macrophages


-Can lyse cells through formation of the membrane-attack complex.

cytotoxic T cells are activated by docking with <BLANK> on the surface of APCs, while helper T cells are activated by docking with <BLANK> on the surface of APCs.

MHC Class I; MHC Class II

______________ antibodies make up the largest group produced during a secondary immune response.

IgG

The variable region of an antibody:

Binds to a specific epitope (antigenic determinant).

Memory cells:

Produce the secondary immune response.

Which of the following is an example of a primary lymph organ?

Thymus gland

Which of the following is a "first line" of defense?

-Mucous membranes in mouth

-Mucous escalator

Which of the following non-specific modes of cell killing is utilized by the specific immune system?

Membrane attack complex (MAC)

Which antibody type is associated with allergic reactions?

IgE

All cells in the human body have:

MHC I on their surface except red blood cells.

Antibodies:

Have the ability to recognize antigens that a person has never been exposed to before.

In response to _____, complement plays a role in _____ by ______.

Antigen-antibody complex; lysis of target cells; the classical pathway

Antigen-Presenting Cells (APCs) include ______ and play the following role:

Dendritic cells; secretion of Interleukin-1 (IL-1)

Cytotoxic T-cells recognize antigen presented by along with .

A viral-infected cell; MHC I protein

Inflammation:

Causes increased capillary permeability.

Breastfeeding babies is important because it allows mothers to:

Induce passive immunity in the baby through IgA in breast milk.

During B-cell activation, helper T-cells:

Bind B-cells and activate them to divide and produce plasma and memory cells.

Injection of anti-venom is an example of:

Passive immunity.

Which of the following best describes a major difference between specific and non-specific defense?

Production of memory cells

Which of the following is an example of active immunity?

The production of antibodies after a flu vaccination

Kinins are _____ mediators which _____.

Inflammatory; allow for chemotaxis

What do mast cells and basophils have in common?

Both secrete histamine

When activated as part of a primary immune response, specific B-lymphocytes:

Divide to form a clone of daughter cells
Differentiate into plasma cells
Differentiate into memory cells

Cytotoxic T-cells become immunocompetent:

After positive and negative selection during fetal development.

Which of the following is true of both cytotoxic and helper T-cells?

Both are immunocompetent due to specific receptors.

The complete absence of macrophages would impair the body's ability to:

-Present antigens after phagocytosis of foreign material.


-Activate helper T-cells.

During a trip to Las Vegas you are bitten by a rattlesnake. You recover only after treatment with snake anti-venom. You plan another trip to the same area this year and you wonder if you are protected against future rattlesnake bites. Are you?

No, because this is an example of passive immunity.

As part of the inflammatory response, neutrophils are able to:

-Move (migrate) to the injured area following the chemical signal of kinins.

-Consume cell debris and dead bacteria.

-"Escape" blood vessels in the area of tissue damage.

Unlike lymphatic nodules, lymph nodes:

Contain lymph.

What is a role of macrophages in the immune response?

-Phagocytosis of debris

-Activation of T-cells

-Antigen presentation