The rejection of a transplanted organ by the immune system of the recipient is a result of a cell-mediated immune response, rather than antibody-mediated response. What does this indicate about the nature of the transplanted cells? From the perspective of the T cell, are the cells of the transplanted organ significantly different from virus-infected or cancerous self cells? Transplanted cells contain surface molecules recognized as self, as well as some recognized as non-self. As far as the T cell is concerned, the transplanted organ consists of altered self cells that are no different from those related to viruses or cancer. Question 2: An industrious 10-year-old swimmer has attached an extension to his snorkel tube, so that he can sit on the bottom of the ocean for a longer period of time, watching the fish of the coral reef. What problems would you expect him to have? Assuming he is successful in breathing this way for a little while, what are some of the differences, he will experience compared to normal breathing? (HINT: Think about dead space)
Question 3: Diabetes mellitus produces many homeostatic imbalances, including acidosis. The pH imbalance is due to ketoacidosis, which results from excessive accumulation of by-products of fat metabolism, as the body cannot meet energy needs from carbohydrate metabolism. Sally is a teenaged diabetic who sometimes rebels by not taking her insulin. Her mother takes her to the hospital because her breathing has become deep and gasping. Explain Sally’s breathing pattern. What other compensatory responses may occur, and would they occur earlier or later than the respiratory response?
Stem cell research is one of the most interesting areas of biology today. Stem cells have two important characteristics that distinguish them from other types of cells. First, they are unspecialized cells that renew themselves for long periods through cell division. The second is that under certain physiologic or experimental conditions, they can be induced to become cells with special functions, ...
Question 4: Mrs. Beck is trying to become pregnant. One of the Becks’ favorite ways of relaxation before ‘doing the deed’ is to soak in the hot tub while drinking wine. A year has gone by with no pregnancy occurring, so they visit your fertility clinic. You conclude that the hot tub is a possible factor in Mr. Beck’s infertility. Angered and insulted, both assure you that they have no difficulty having intercourse, unless Mr. Beck has had too much wine, which happens infrequently. How will you explain to them the difference between impotence and infertility? Why should you suspect the hot tub as a factor in Mr. Beck’s lowered sperm count?