Chapter 24

Foreign molecules that elicit an immune response are called a. major histocompatibility complex (MHC) molecules. b. antibodies. c. histamines. d. antigens.

Which of the following is mot part of the vertebrate innate immunity defense? a. macrophages b. antibodies c. complement system d. Inflammation

Which of the following best describes the difference in the way B cells and cytotoxic T cells deal with invaders? a. \(B\) cells confer active immunity; \(T\) cells confer passive immunity. b. B cells send out antibodies to attack; certain T cells can do the attacking themselves. c. T cells handle the primary immune response; B cells handle the secondary response. d. B cells are responsible for the cell-mediated immune response; T cells are responsible for the humoral immune response.

Cytotoxic T cells are able to recognize infected body cells because a. the infected cells display foreign antigens. b. the infected cells produce antigens. c. infected cells release antibodies into the blood. d. helper T cells destroy them first.

What is inflammation? How does it protect the body? Why is inflammation considered part of the innate immune response?

In the condition myasthenia gravis, antibodies bind to and blocb certain receptors on muscle cells, preventing muscle contraction This condition is best classified as an a. immunodeficiency disorder. b. exaggerated immune reaction. c. allergic reaction. d. autoimmune disorder

Which of the following statements is not true? a. An antibody has more than one antigen-binding site. b. An antigen can have different epitopes. c. A lymphocyte has receptors for multiple and different antigens. d. A bacterium has more than one antigen.

Propose an explanation for why we need a flu shot year after year, instead of only once early in life.

Pertussis (whooping cough) is caused by a bicterial infection, and symptoms include an intense cough that lasts for weeks, sometimes leading to pneumonia and death. A complete vaccination against pertussis requires five doses, completed by age 5 . A pertussis outbreak occurred in Callifornia in 2010 , and a news article reported the following "Among fully immunized kids, there were about 36 cases for every 10,000 children two to seven years old, compared to 245 out of every 10,000 kids aged eight to twelve." Propose an explanation for these data and a public health solution based on your explanation.

Your roommate is rushed to the hospital after suffering a severe allergic reaction to a bee sting. After she is treated and released, she asks you (the local biology expert!) to explain what happened. She says, "I don't understand how this could have happened. I've been stung by bees before and didn't have a reaction." Suggest an explanation for what has happened to cause her severe allergic reaction and why she did not have the reaction after previous bee stings.

Organ donation saves many lives each year, Even though some transplanted organs are derived from living donors, the majority come from patients who die but still have healthy organs that can be of value to a transplant recipient. Potential organ donors can fill out an organ donation card to specify their wishes. If the donor is in critical condition and dying, the donor's family is usually consulted to discuss the donation process. Generally, the next of kin must approve before donation can occur, regardless of whether the patient has completed an organ donation card. In some cases, a family member overrides the donor's wishes. Do you think that family members should be able to overrule the stated intentions of the potential donor? Why or why not? Have you signed up to be an ongan donor? Why or why not?

One of the key difficulties in the development of anti-HIV drugs is the fact that HIV only infects humans. This precludes the testing of drugs in animals and instead requires that drugs be tested on volunteer human subjects. The developing world (particularly sub-Saharan Africa and Southeast Asia) has the highest rates of HIV infection. Consequently, drug companies frequently conduct studies in these regions. Some people decry such tests, fearing that drug companies may profit hugely from the use of economically disadvantaged people, Others counter that such tests are the only way to find new and cheaper drugs that will ultimately help everyone. What do you think are the ethical issues surrounding trials of anti-HIV drugs in the developing world? Which side do you think has the more morally compelling argument?