Chapter 29 Practice Questions

The region of an antibody molecule that recognizes and binds to an antigen is the...

variable region

If a human fetus is _______ and the pregnant woman is _______, an incompatibility that destroys the red blood cells of the fetus may occur.

Rh-positive; Rh-negative

Which of the following are examples of humoral immunity?

antibodies produced that destroy an invading pathogen

A Y-shaped protein that is produced in response to a specific antigen and recognizes these antigens is a(n)...

antibody

In a process called _______, an army of plasma cells and memory cells are produced from properly-stimulated B cells.

clonal selection

The primary function of a vaccine is to...

create immunological memory without causing disease

Which of the following is not attacked by the immune system as an intruder in humans?

dead skin cells

In the section "Investigating Life: The Hidden Cost of Hygiene", flatworms are very thin and lack a specialized respiratory or circulatory system. How does oxygen reach their cells?

diffusion through the wall of their body

B cells or T cells are...

lymphocytes

Every year the common flu vaccine is designed to protect against three different strains of the influenza virus.

recombination of the gene used to make antibodies occurs

A patient can have antibodies against many strains of HIV. Which of the following is the main reason that an effective vaccine has not been produced for the HIV virus that causes AIDS?

the virus mutates rapidly, changing its outer coat

Why would AIDS patients infected with HIV be at risk for opportunistic infections and rare cancers?

their immune systems are suppressed

Why would HIV infection lead to immunodeficiency?

HIV infects helper T cells

If you transfuse type AB blood into a patient with type A blood, the patient will raise antibodies against the B antigen on the donor's blood, but will not raise antibodies against the A antigen. Why not?

B and T cells that recognize the A antigen will have been removed by clonal deletion

Which of the following correctly describes B cells and T cells?

B cells and T cells are lymphocytes

Antibodies are made against a very small portion of an antigen called an epitope. An epitope is often just 5-6 amino acids from a protein on an antigen. Which of the following explains how antibodies could be produced against just a small part of an antigen?

B cells produce antibodies that bind directly to a single epitope on the antigen

White blood cells are produced...

from bone marrow stem cells

Although the lymphatic system has many similarities to the circulatory system, what can the lymphatic system accomplish which the circulatory system cannot?

generate white blood cells

HIV-positive people track the progress of their disease with blood tests that measure the number of...

helper T cells

The "master cells" of the immune system that initiate and coordinate the adaptive immune response are...

helper T cells

The innate chemical substance produced by basophils that causes blood vessels to dilate is...

histamine

Which of the following descriptions is correctly matched with its term?

innate defenses: able to defend against any pathogen

The innate chemical substance that alerts other cells and components of the immune system to a viral infection is...

interferon

The innate chemical defense substance that activates T cells and B cells is...

interleukin

The presence of antibodies against HIV can be used to diagnose an infection that has occurred at least three months earlier. Why couldn't the presence of antibodies against HIV be used to diagnose a more recent infection?

it takes two to three months to raise antibodies against the virus

A primary "antigen presenting cell," a cell that presents an antigen to a helper T cell, is a...

macrophage

A cell that does not circulate in blood, but instead settles in tissues near the skin and in the digestive tract, producing and releasing histamine when tissue is damaged, is a...

mast cell

A disease-causing agent that does not usually infect and cause disease in a person with a healthy immune system is termed a(n)...

opportunistic pathogen

Which of the following is not considered to be a major part of the immune system?

pancreas

In the section "Investigating Life: The Hidden Cost of Hygiene", what is the hygiene hypothesis?

people who have fewer infections will have an overactive immune system

Special cells produced by the immune system that are progeny of properly-stimulated B cells and are antibody-producing factories are...

plasma cells

Which of the following is a method in which a pathogen can enter a vertebrate and the immune system defends against it?

sneezing viruses parasites kissing

Which of the following vaccines would expose a person to an antigen for the longest time, and thus be the least likely to require repeated booster vaccinations?

subunits of pathogens

Physical and chemical barriers that form the first line of innate defense include...

the acidity of the stomach tear fluid from the eye un-punctured skin mucus and cilia of the respiratory tract

A preparation that "teaches" the immune system to recognize a disease-causing agent without actually causing disease it termed a(n)...

vaccination

Why is there potential for a woman's body to recognize her fetus as foreign?

the fetus and mother are not genetically identical

Each year there are an estimated 250,000 people who could benefit from a bone marrow transplant. A major challenge is finding a donor with the matching complex of Major Histocompatibility (MHC) proteins a person needs. Why is it important that the MHC proteins match between the donor and recipient?

MHC proteins make antibodies which could attack the recipient's immune system

In the section "Investigating Life: The Hidden Cost of Hygiene", which of the following occurred during the coevolution of humans and pathogens that causes disease?

the pathogens produce substances that suppress our immune system

How does the immune system recognize pathogens it has fought before?

the primary immune response creates memory B and memory T cells which are activated in a secondary immune response

Which of the following is correct about primary and secondary immune responses?

the primary immune response occurs first the primary immune response is smaller both respond to foreign antigens both are responses of adaptive immunity

Each year there are an estimated 250,000 people who could benefit from a bone marrow transplant. What would happen to a patient who no longer had active bone marrow?

they would be immunocompromised

Why do lymph nodes often become swollen during an infection?

T cells reproduce in lymph nodes after being exposed to pathogens

Many parasites are too large to be engulfed by phagocytosis. Which of the following would be effective in killing parasites?

T helper cells

The role of B cells in adaptive immunity is _______, versus the role of T cells in adaptive immunity is _______.

to recognize a specific antigen; to recognize any antigen

Which of the following are examples of passive immunity?

a fetus acquiring antibodies through the placenta, or a person receiving an injection of antibodies

Rh incompatibility is due to an immune reaction to which of the following by a pregnant woman?

a foreign antigen on red blood cells

Which of the following is a major difference between adaptive immunity and innate defenses?

adaptive immunity responses are produced only on demand; innate defenses are always produced

An exaggerated attack on a harmless antigen by an overly-sensitive immune system is termed a(n)...

allergy

In many autoimmune diseases such a lupus and rheumatoid arthritis, antibody complexes form in the blood. Kidney failure is a common consequence of these diseases for which reason?

antibodies attack the kidney

Which of the following are examples of active immunity?

antibodies produced from a vaccine, or a person receiving an injection of antibodies

Which of the following is not part of the innate defense response?

antibody production

A molecule that stimulates an immune-system reaction by B cells and T cells is termed a(n)...

antigen

In the section "Investigating Life: The Hidden Cost of Hygiene", which of the following would a person in a less-developed country be less likely to have than a person in a more-developed country, according to the hygiene hypothesis?

asthma

If a tumor metastasizes, this means that it has moved to another part of the body. Doctors often look in lymph nodes near a tumor for signs of metastasis. Why might cancer cells be found in lymph nodes?

because the lymphatic system collects fluids and cells from tissues

Every year the common flu vaccine is designed to protect against three different strains of the influenza virus. Why do scientists typically have to make a new vaccine every year?

because the virus develops resistance to the vaccine

Immunological memory results from the production of...

both B and T memory cells

Histamine triggers vasodilation and leakiness in blood vessels during inflammation. Why would this be beneficial in fighting an infection by a pathogen?

both increased number of white blood cells and their migration to site of infection

Which of the following would occur if the lymphatic system was absent?

cancer would not spread as quickly because cancerous cells would not be transported by the lymphatic system, nor stored in lymph nodes bacteria located in the body would not be destroyed if they were not in the blood viruses located in the body would not be destroyed if they were not in the blood cancer cells located in the body would not be destroyed if they were not in the blood

A phagocyte is a...

cell that engulfs other cells and debris

The substance that when activated triggers a chain reaction that punctures bacterial cell membrane is...

complement protein

Which of the following is a reason why fever is considered a defense mechanism?

fever inactivates (kills) some viruses fever speeds up the rate of phagocytes fever reduces the iron level in the blood, thereby retarding the growth of some bacteria fever kills some bacteria