Biology - MG2

Eukaryotic telomeres replicate differently than the rest of the chromosome. This is a consequence of which of the following? a. Gaps left at the 5' end of the lagging strand because of the need for a 3' onto which nucleotides can attach b. DNA polymerase that cannot replicate the leading strand template to its 5' end c. The evolution of telomerase enzyme d. Gaps left at the 3' end of the lagging strand because of the need for a primer

a

In the late 1950s, Meselson and Stahl grew bacteria in a medium containing "heavy" nitrogen (15N) and then transferred them to a medium containing 14N. Which of the results in Figure 16.1 would be expected after one round of DNA replication in the presence of 14N? Select one: a. A b. D c. B d. C e. E

b

In a linear eukaryotic chromatin sample, which of the following strands is looped into domains by scaffolding? Select one: a. the 10 nm chromatin fiber b. DNA without attached histones c. the 30 nm chromatin fiber Correct d. DNA with H1 only

c

Why do histones bind tightly to DNA? Select one: a. Histones are covalently linked to the DNA. b. Both histones and DNA are strongly hydrophobic. c. Histones are positively charged, and DNA is negatively charged. Correct d. Histones are negatively charged, and DNA is positively charged.

c

In an experiment, DNA is allowed to replicate in an environment with all necessary enzymes, dATP, dCTP, dGTP, and radioactively labeled dTTP (3H thymidine) for several minutes and then switched to nonradioactive medium. It is then viewed by electron microscopy and autoradiography. The drawing below represents the results. Which is the most likely interpretation? Select one: a. Thymidine is only being added where the DNA strands are furthest apart. b. Thymidine is only added at the very beginning of replication. c. Replication proceeds in one direction only. d. There are two replication forks going in opposite directions.

d