Exam 13: Dna and Its Role in Heredity

If one strand of DNA has a C attached to a sugar with a free 5 phosphate group, the other strand will have a _______ attached to a sugar with a free _______ group.

In many eukaryotes, there are repetitive sequences called telomeres at the ends of chromosomes.After successive rounds of DNA replication, the _______ strand becomes shorter.In some cells, an enzyme called _______ repairs the shortened strand. a. lagging; telomerase b. leading; DNA polymerase I c. leading; replicase d. lagging; DNA polymerase I e. leading; telomerase

If 28 percent of the bases in a sample of DNA are T, _______ percent must be G.

Refer to the figure, which shows DNA replication. Which diagram (A or B) shows semiconservative replication?

If Hershey and Chase had found ³²P in both the pellet and the supernatant of the phage-infected bacteria, what would have been their likely conclusion about the nature of genetic material?

Refer to the figure of a DNA molecule. One can deduce all of the following information from this image except

If a sequence in one strand of DNA is 5ʹ-AGCTGCTGA-3ʹ, what is the sequence in the complementary strand?

If the Meselson-Stahl density gradient experiment had resulted in two bands of DNA molecules after only one round of replication, one containing only ¹⁵N and the second only ¹⁴N, this result would have indicated that replication was a. conservative. b. dispersive. c. bidirectional. d. semiconservative e. unidirectional.

In organisms that contain circular DNA,

A researcher would like to separate viral DNA from the viral coat proteins using a density gradient.Which material would she use to set the density gradient?

What prevents the DNA repair system from "repairing" telomeres?

If a single cycle of PCR takes 5 minutes, how long should it take to amplify one double-stranded molecule into 64?

The nucleotides that make up a DNA molecule each contain _______ phosphate group(s).Before they are added to the DNA, the precursors to nucleotides each contain _______ phosphate group(s).

Bacteria from hot springs greatly helped the development of PCR by

Which feature of DNA replication is a consequence of semiconservative replication?

You are a biologist working with a cell culture.You notice that the chromosomes are decreasing in size with each cell division.Other than that, the cells seem healthy.What is the most likely explanation?

The "P" in "PCR" stands for _______.

Refer to the figure, which shows DNA complementary base pairing. Explain the difference between conservative and semiconservative models of DNA replication.What were the experimental results that supported the semiconservative model? What would the results have looked like if the conservative model of DNA replication had been accurate? Are there any other potential hypotheses?

Researchers have determined the chemical composition of a molecule that interacts with DNA.To understand how it binds to a DNA molecule, the researchers can utilize _______ to deduce the physical structure of the molecule.

If the enzyme _______ were nonfunctional, the double helix would not be able to unwind and separate into single strands.