Why does a microaerophilic organism grow only in the middle depth region of a fluid thioglycollate medium tube?
A. The organism is not dense enough to sink to the bottom
B. The organism cannot grow in the presence of the resazurin
C. The tube has a gradient of dissolved oxygen and the organism requires intermediate levels
D. Nutrients are not available at the bottom of the tube
Answer: C. The tube has a gradient of dissolved oxygen and the organism requires intermediate levels
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In transduction, bacterial cells
a. take up pieces of DNA that are released as other cells disintegrate. b. take up pieces of DNA through the use of a virus. c. replicate DNA molecules. d. make replicate copies of one another. e. generate their own DNA.
Darwin concluded from his observations of nature and readings that
A. species do not change over time. B. individuals compete with one another for limited resources and only the fittest survive and reproduce. C. individuals compete with one another for limited resources and only the fittest survive. D. an individual's likelihood of survival and reproduction are mostly due to chance and changes in the environment. E. population growth is unlimited, leading to the large numbers of organisms.
Darwin's assumption that living forms must be descended from extinct forms was based on ________ evidence.
A. anatomical B. biogeographical C. fossil D. biochemical
Which of the following apply to the tomato example?
A. Transgenic Organism B. Recombinant DNA C. Genetically modified organism D. All of the above