Bio Chapter 24

How do memory cells differ from effector cells?

Memory cells live longer Memory cells live longer than effector cells and are responsible for the secondary immune response. Your immune system responds slowly to newly encountered pathogens. But memory cells allow your immune system to respond much more rapidly to pathogens that it has seen before.

_______ circulate through the bloodstream and engulf foreign cells, foreign molecules, and debris from dead cells.

Phagocytic cells

Why do diseases involving widespread infection often result in a fever?

The brain's temperature control center responds to inflammation by creating a hot environment unfavorable to the growth of microorganisms.

Viruses and bacteria in body fluids are attacked by __________.

antibodies produced by B cells Circulating antibodies encounter microorganisms and viruses in body fluids and quickly complex with them.

A substance that can elicit an immune response from a lymphocyte is called a(n) ______.

antigen

Histamine ______.

attracts phagocytic cells

How was HIV first linked to AIDS?

by detecting antibodies to HIV in the bloodstreams of AIDS patients

The major result of the inflammatory response is to ______.

disinfect and clean damaged tissues

Natural killer (NK) cells __________.

do not attack microorganisms directly; instead, they destroy virus-infected body cells or cancer cells

When a B or T cell is primed by an interaction with its particular antigen, the cell ______.

grows, divides, and differentiates further

Which of the following cell types does HIV preferentially infect?

helper T cells

When you cut yourself, the damaged cells immediately release which of the following chemical alarm signals?

histamine

Which of the following compounds do mast cells produce?

histamine

Which of the following is a chemical molecule that causes blood vessels to dilate and leak fluid into a wound, causing it to swell?

histamine

The biggest difference between cell-mediated immunity and humoral immunity is __________.

how they respond to and dispose of invaders

Which of the following is a response of our innate defense system?

inflammation

Which of the following is a protein produced by virus-infected body cells, which helps uninfected cells resist viral infection?

interferon

Humans that are infected with avian influenza are likely to have elevated levels of ______.

interferons

The two main functions of the _____ are to return tissue fluid to the circulatory system and to fight infection.

lymphatic system

Which of the following cell types initiates a secondary immune response?

memory cells

A humoral-type secondary immune response differs from the corresponding primary immune response in that the secondary response ______. -is slower -results in fewer antibodies in the blood -is able to target microorganisms even if they have altered their surface antigens -none of the above

none of the above

Which of the following substances does a cytotoxic T cell secrete to destroy a target cell?

perforin

What kinds of cells engulf whatever foreign cells and molecules they encounter and recognize?

phagocytic cells

Antibodies are ______.

proteins consisting of four polypeptide chains

The primary immune response ______.

results in the production of short-lived effector cells via clonal selection

A role of the lymphatic system is to ______.

return tissue fluid to the circulatory system

Tissues are typed before an organ transplant to make sure that the _____ of donor and recipient match as closely as possible.

self proteins

The immune system is the body's system __________.

that defends against infectious disease

The immune system is capable of mounting specific responses to particular microorganisms because ______.

the body contains an enormous diversity of lymphocytes, each with a specific kind of antigen receptor

The functions of antibodies include ______.

the clumping of invader cells

Diagram

37,38,40

An antigen is __________.

a foreign molecule that evokes an immune response

Every day about 7,000 people worldwide are infected with HIV. AIDS is the fourth leading cause of death in low-income countries. After almost 30 years of research, there are treatments, but there is still no practical and effective vaccine and still no cure. Which of the following statements reflects what we know about HIV, AIDS, and AIDS-related research?

Antibiotics are ineffective against viruses, such as HIV.

Which of the following cell types are specifically responsible for humoral immunity?

B cells

One kind of vaccine consists of a solution containing ______.

a harmless variant of a disease-causing microbe

Which of the following cells would be active during an immune response to a viral infection? Read the following scenario to answer the following question. Avian influenza is a viral infection that naturally occurs in wild birds with few damaging effects. However, avian influenza is highly contagious and can quickly kill domesticated birds. Some human influenza viruses are similar to the avian influenza. People infected with avian influenza develop typical flu symptoms (fever, cough, muscle aches). However, symptoms may become more severe and life-threatening. If avian influenza evolves into a form that is easily transmissible from person to person, a global pandemic of widespread human death might occur. Which of the following cells would be active during an immune response to a viral infection? T cells natural killer cells phagocytic cells all of the above

all of the above

Antigens that cause allergies are called _____.

allergens

When the immune system improperly turns again the body's own molecules, the result is _____.

an autoimmune

What has caused the evolution of drug-resistant strains of HIV?

anti-AIDS drugs

After binding to antigens, B cells differentiate into short-lived cells that secrete _____.

antibodies Antibodies interact specifically with the antigen to form an antigen-antibody complex.

When in its life cycle does a B cell first exhibit its particular surface antibody?

before it ever encounters an antigen

The role of cytotoxic T cells is to attack __________.

cancer cells and infected body cells

Anaphylactic shock ______.

causes blood pressure to drop dangerously

The basic function of T cells is to identify and destroy invaders in our ______.

cells

Examine the numerous long structures extending from the surface of some of the cells in the following figure. Cells with these long structures could be found lining ______.

the trachea