In Fredrick Griffith's classic experiments,
A. mice injected with strain R cells died of pneumonia.
B. mice injected with strain S cells died of pneumonia.
C. mice injected with live strain R cells and heat-killed strain S cells died of pneumonia.
D. mice injected with strain S cells, or live strain R cells and heat-killed strain S cells died of
pneumonia.
E. mice injected with strain R cells, or live strain R cells and heat-killed strain S cells died of
pneumonia.
D
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Describe the secondary response to an antigen
What will be an ideal response?
Four of the five outcomes listed below are related to
the accumulation of oxygen in the atmosphere. Select the exception. a. Further chemical origin of living cells stopped. b. Chemical attacks by oxygen radicals stopped. c. Aerobic respiration evolved. d. With few exceptions, complex organic compounds could no longer form. e. Some cells detoxified oxygen by using it to accept electrons.
If a man and his wife are affected with a dominant trait, then ____________________ of their children
could be unaffected. Fill in the blank(s) with the appropriate word(s).
Which of the following has the greatest potential as a cancer treatment?
A. Find a way to turn on the gene for making telomerase in normal cells, so that the normal cells would soon outnumber the cancer cells. B. Find a way to turn off the gene for making telomerase in cancer cells, since the cells would stop dividing when the telomeres were gone. C. Find a way to turn off the gene for making telomerase in all cells in embryos, so that they never develop cancer. D. Find a way to turn on the gene for making telomerase in cancer cells, since they will be unable to divide if their telomeres are too long.