lymphatic system

Which one type of cells are responsible for producing and releasing antibodies?

B lymphocytes

Why do some physicians advise patients with a bladder infection to drink a lot of cranberry juice?

Cranberry juice makes the urine more acidic, decreasing the rate at which microorganisms can grow and reproduce.

Viral infections can usually be treated with antibiotics.

False: Antibiotics are ineffective against viral infections because antibiotics target bacterial cell structures or functions that are absent in viruses.

The best way to reduce bacterial pathogens in the bloodstream is to reduce a fever as quickly as possible.

False: Fever is a response that helps the body fight infections by inhibiting bacterial growth and enhancing immune function. Treating fever does not directly reduce bacterial pathogens in the bloodstream.

When considering transfusions or transplants, it is more difficult to match blood than to match tissue types because blood cells have more self markers on their surface.

False: Matching blood types (specifically ABO and Rh factors) is crucial to prevent adverse reactions during transfusions, but tissue matching for transplants (like organs) involves compatibility of major histocompatibility complex (MHC) proteins, which are more complex than blood group antigens.

Which of the following antibodies would most likely be involved with the immune response against a microorganism entering the digestive or reproductive tract?

IgA

Which of the following classes of antibodies activates the inflammatory response by causing the release of histamine?

IgE

All of the following are involved in the generation of an allergic response EXCEPT which one?

IgG

Antibodies are classified by size, location, and function, and which one of the following represents the most common type of immunoglobulin?

IgG

Body defenses that respond to generalized tissue damage and many common pathogens are referred to as

Nonspecific mechanisms

Which of the following is TRUE regarding HIV and AIDS?

Symptoms of AIDS do not normally appear until years after HIV detection.

Which one of the following types of T cells is a critical component of the immune system because it stimulates and enhances the activity of other components of the immune system?

T helper cell

Which immune system cell must be presented with antigen by an antigen-presenting cell such as a macrophage, in order to become appropriately activated?

T lymphocyte

Once a macrophage engulfs a bacterium, what happens to the foreign cell?

The bacterium is killed by digestive enzymes released from lysosomes.

Which one of the following is correct regarding the structure of an antibody?

The four polypeptide chains that make up an antibody molecule are linked by disulfide bonds.

An individual with an uncertain vaccine history has been brought to the emergency room after receiving severe lacerations in an accident with farm machinery. In addition to administering a tetanus toxoid vaccine, he is also given a shot of tetanus immune globulin (TIG), a form of passive immunization. Why are both necessary?

The tetanus immune globulin provides immediate, short-term protection, and the tetanus vaccine provides long-term protection.

Which one of the following best explains why people get so many colds in their lifetime?

The viruses that cause colds evolve rapidly, which results in a change in their antigenic structure.

The figure above illustrates antibody titers produced during a primary and secondary immune response. All of the following statements about the primary and secondary immune response are correct EXCEPT which one?

There is a lag time between antigen exposure and antibody production in the primary immune response that is not seen in the secondary immune response.

Which one of the following is TRUE regarding lymph nodes?

They filter lymph fluid, trapping microorganisms and abnormal cells.

When comparing viruses and bacteria, which one of the following statements is CORRECT?

Viruses and bacteria both contain genetic material.

Which one of the following is TRUE regarding the spleen?

White pulp of the spleen contains macrophages that kill microorganisms circulating in the lymph

Developing strategies for treating HIV infection and preventing AIDS in sub-Saharan Africa have been complicated by

a complex network of roads for travel to villages

Any substance that produces an inappropriate response of the immune system is referred to as a(an)

allergen

All of the following represent physical and/or chemical barriers that form the body's first line of defense against pathogens EXCEPT which one?

antibodies

Identify the figure above.

antibody

Vaccines contain

antigens of the pathogen

Antibiotics are most likely to be effective in the treatment of infections caused by

bacteria

The bubonic plague epidemic that swept through Europe between 1348 and 1350 A.D. was induced by a(n)

bacterium

Once a prion enters a nerve cell, it essentially

becomes self-propagating, causing misfolding of nearby normal proteins

Which of the following is associated with the specific defenses of the body?

cell-mediated immunity

Which of the following are proteins in the blood, which when activated can lyse bacterial cells, mark other bacterial cells for destruction, and enhance inflammation?

complement

Which one of the following enables T helper cells to stimulate and activate other cells of the immune response?

cytokines

Bacteria are helpful to humans in many ways, including all of the following EXCEPT which one?

digestion of cellulose in the human intestine

Which one of the following is characteristic of T lymphocytes but NOT B lymphocytes?

direct attack of antigen-bearing cells

) Referring to the figure above, the progression from Phase II HIV infection to Phase III is marked by

drop in the helper T cell count to less than 200/mm3

All of the following are ways in which a mild fever participates as part of the body's second line of defense and aids the body EXCEPT

enhancing the secretion of antibodies by plasma cells

Which of the following leukocytes is most likely to be directly involved in the destruction of flukes (a parasitic flatworm)?

eosinophils

Skin is able to prevent most microorganisms from entering the body by

having keratin in the uppermost layer

The advantage of having memory cells in specific defenses is that

if exposed to an antigen a second time, they quickly become plasma cells

Viral-infected human cells often send out special proteins that serve as an early warning system to uninfected cells. In response, the uninfected cells develop antiviral proteins that protect them. The early warning proteins sent out by viral-infected cells are

interferon

Passive immunity differs from active immunity in that passive immunity

involves the administration of preformed antibodies

All of the following are routinely done to assure a successful organ transplant and minimize the chance of organ rejection EXCEPT which one?

irradiate the recipient to knock out his or her immune system prior to the transplant

HIV is classified as a retrovirus because

it makes a DNA copy of its RNA once inside the host cell

Lupus erythematosus is an autoimmune disorder in which the body attacks

its own connective tissue

The release of chemicals from injured cells triggers histamine release from

mast cells

All of the following are used in the production of monoclonal antibodies EXCEPT which one?

mouse T cells

Which one of the following would result in passive immunity?

movement of antibodies across the placenta from mother to child

Which of the following leukocytes kills its target cells, such as cancer cells or virus-infected cells, by releasing chemicals that break down the target cell membrane?

natural killer cells

During cytotoxic T cell attack of a target cell, which one of the following is released to pierce the cell membrane of the foreign cell, which ultimately kills the target cell?

perforin

Which one of the following diseases is caused by a virus?

rabies

Which of the following body fluids does not transmit HIV from human to human?

saliva

Bacterial pathogens cause symptoms of a disease by invading host cells or by producing toxins that damage host cells.

true

Individuals infected with HIV produce antibodies, but these antibodies don't prevent progression to Phase II and Phase III of infection.

true

One role of MHC proteins is that they serve as self markers to the human immune system

true

Prions are infectious proteins that cause normal proteins in the brain to misfold.

true

Tears and saliva contain the enzyme dermicidin, which is effective in preventing bacteria from entering the human body.

true

The bacteria that normally live on the mucous membranes of the digestive tract and vagina provide protection against infection with harmful disease-producing microorganisms.

true