What prevents pathogens from entering our bodies through the delicate tissues

16 Jun What prevents pathogens from entering our bodies through the delicate tissues

Question
(1) What prevents pathogens from entering our bodies through the delicate tissues of the lungs?

a. the lining of the lungs has a low pH that creates an inhospitable environment for most pathogens.

b. the tubes entering the lungs are lined with mucus that traps pathogens and is then removed from the respiratory system.

c. the cells of the lungs are covered by several layers of dead cells that prevent pathogens from getting to living lung tissue.

d. certain cells in the lungs produce toxins that paralyze pathogens before they can infect the body.

(2) Any pathogens that macrophages find indigestible can be isolated from other cells by

a. phagocytosis.

b. producing antigens.

c. producing antibodies.

d. encapsulation.

(3) At the site of a wound or cut, platelets combine with proteins in our blood to form

a. macrophages.

b. antibodies.

c. prostaglandins.

d. clots.

(4) An autoimmune disease would occur if

a. b cells fail to recognize B cells.

b. helper T cells fail to bind to infected cells.

c. B cells and T cells fail to recognize “home team” cells.

d. antibodies from a virus are reactivated in “home team” cells.

(5) Which of the following would explain why doctors are very careful to match certain DNA sequences in an organ donor to those of an organ recipient in the case of a necessary organ transplant?

a. The DNA of a person determines what specific antibody a person makes. In the case of an organ transplant, you want to make sure that the antibody made in the new organ did not react with the antibody made by the recipient.

b. the structures on the surface of cells are determined by DNA, and if the surfaces of the cells of the donor and the recipient are different, the recipient’s immune system may attack the new organ.

c. different DNA sequences may cause the donor and the recipient to produce different strains of interferon, which would result in an autoimmune disease.

d. antibodies can travel through cells to the nucleus and will attack DNA that does not have the self sequence. This can cause organ rejection.

(6) Why is it important that white blood cells are able to travel outside the human circulatory system?

a. in order to form a complement, white blood cells must leave the circulatory vessels.

b. white blood cells are the antibodies that target parasites.

c. pathogens may be found in areas of the body other than within circulatory vessels.

d. white blood cells must leave the circulatory system in order to return red blood cells to the circulatory vessels.

(7) Histamine

a. makes capillaries near a wound more porous.

b. is converted to prostaglandin near a wound.

c. closes down arterioles near a wound.

d. is an antibody.

(8) The fetus of a lion receives antibodies that were produced by its mother while it was still in the womb. This is an example of

a. active immunity.

b. a secondary immune response.

c. a primary immune response.

d. passive immunity.

(10) Which of the following statements about fighting invasions of disease-causing agents in humans s false?

a. the organism must be able to distinguish between itself and foreign invaders.

b. antibodies are produced.

c. antibodies result in the production of antigens.

d. cells engulf some of the invaders.

(11) Active immunity results from injecting

a. a harmless form of a pathogen/.

b. live pathogens.

c. live B cells from another person.

d. antibodies.

(12) __________ on the surface of disease organism help the vertebrate immune system recognize the specific invader.

a. platelets

b. antigens.

c. lymphocytes

d. antibodies

(13) Which of the following statements about infection by HIV, the virus that causes AIDS, is false?

a. most AIDS victims go through a period of up to 15 years between infection and the onset of AIDS symptoms.

b. in the early part of the infection, killer T lymphocytes destroy helper T lymphocytes infected by the virus.

c. the antigens of the protein coat of the HIV remain the same through time.

d. the victim’s immune system eventually collapses, and normally harmless infections cause death.

(14) Fevers are a defense mechanism that helps our bodies fight off invading parasites. Based on this information, should you “starve a fever”?

a. yes, because the reduced food intake will allow the body to generate more energy to fight off the parasite.

b. yes, because eating feeds the infecting parasite more than it feeds the host.

c. no, because foods that are good for humans are toxic to our parasites.

d. no, because the body needs food in order to generate enough metabolic heat to maintain the fever.

(15) Which of the following statements correctly describes the immune response when the invading organism is a virus?

a. the antigen molecules on the viral DNA allow the immune system to prevent the infection.

b. lymphocytes are not involved in the immune response.

c. the lack of nucleic acid in virus complicates the immune response.

d. lymphocytes respond to infected human cells rather than to the virus itself.

(16) During a major infection, you get a high fever because

a. the bacteria in your body produce chemicals that cause the brain to raise your temperature to make the environment more appropiate to bacterial gorwth.

b. your immune system signals the brain to raise body temperature to limit bacterial growth and speed up phagocytosis.

c. pathogens damage tissues throughout your body, causing an extreme inflammatory response.

d. your low energy levels prevent the brain from maintaining the negative feedback loop that controls body temperature.

(17) Once B cells become effector cells, they

a. produce the antigens that attach to antibodies.

b. release free-standing antibodies.

c. release free-standing antigens.

d. bind to infected T cells.

(18) Which of the following statements about the human immune response is true?

a. host cells are never destroyed by macrophages, even if they are damaged.

b. neutrophils mount a specific response to particular species of invading organisms.

c. the immune response is more effective during the second exposure to an invader.

d. lymphocytes are one of the components of blood clots.

(19) Killer T cells

a. directly kill viruses.

b. kill cells that are infected by viruses.

c. cause B cells to proliferate when they are bound to their antigen.

d. bind to B cells and then to infected cells.

(20) Which of the following statements about vaccinations given to humans is true?

a. the vaccination acts as the first exposure to a virus, allowing the much more effective second exposure response to occur when the virus actually infects the body.

b. a vaccination primes the body so that it will no longer respond to an invasion by a virus.

c. there is a chance of a person’s getting the disease from a vaccination, since vaccination involves the injection of the entire living disease organism.

d. vaccinations prime the virus so that they virus will not kill as many blood cells as it would in an unvaccinated person.