Exam 1 with answer key

Exam 1 with answer key - Biology 142 Exam 1 02/24/12...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 of 8 Biology 142 Exam 1 02/24/12 CAFFERTY Honor Signature____________________________Name (printed)______________________ By signing above you are accepting the honor code of the University and acknowledging that all work turned in must be entirely your own. Copying answers or aiding someone else copying your answers could result in your suspension from the college. INSTRUCTIONS - Bubble in your name and ID on the scantron. Sign your exam. - Choose the single, best answer. - You may mark your answer on the exam question sheet, but only the scantron will be graded. Only your exam will be returned to you. - No questions can be answered during the exam. If there are any problems with a question, please bring them to the professor’s attention when the exams are returned to you. - When instructed, pass your scantron, then your exam, toward the front of the room.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 of 8 1. In 1946, Lederberg and Tatem inoculated supplemented-growth medium with two different multiply auxotrophic E. coli strains. Following the co-culture of these strains overnight, they spread the bacteria on agar plates with minimal media and observed the growth of a small number of prototrophs. They suggested that conjugation and recombination had occurred between the two initial auxotrophic strains because: A. This is the only possible explanation for the generation of prototrophic cells. B. The probability of spontaneous mutations is impossible. C. They couldn’t think of anything else. D. The process of F factor mediated conjugation was well understood. E. none of the above 2. A ____________ strain of Streptococcus thermophilus can grow on minimal medium containing one carbohydrate source, two metallic ions, six vitamins, urea, and six amino acids. A. mutant B. auxotrophic C. leaky D. competent E. prototrophic 3. The process of conjugation always involves: A. the recombination of a DNA fragment into the main chromosome of the recipient cell. B. the transfer of DNA from a donor cell to a recipient cell. C. the transfer of the entire bacterial chromosome from the donor cell to a recipient cell. D. an absence of physical contact between donor and recipient cells. . E. All of the above. 4. Imagine you are conducting a mating experiment similar to that of Zinder and Lederberg by co- culturing two different multiple auxotrophic Salmonella typhimurium strains in the Davis U-tube. You predict, due to the presence of a filter preventing direct contact of the two bacterial strains, that bacteria taken from each side of the U-tube following incubation will be unable to grow on minimal media. To your surprise, you observe that bacteria cultured from the right side of the U-tube are able to grow on minimal media. This result suggests that chromosomal material could have been transferred by: A. some mechanism of DNA transfer that requires the direct contact of bacterial cells. B. transduction.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 8

Exam 1 with answer key - Biology 142 Exam 1 02/24/12...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online