Critical Thinking

47.

In the figure shown, if the nuclei were contained within the stalks of Acetabularia, what types of caps would you expect from the pictured grafts?

A diagram showing a. mediterranea and A. crenulata. Graft A is of the foot of A. mediterranea and the upper stalk of A. crenulata. Graft B is of the foot of A. crenulata and the upper stalk of A. mediterranea.

48.

Why are Hershey and Chase credited with identifying DNA as the carrier of heredity even though DNA had been discovered many years before?

49.

A certain DNA sample is found to have a makeup consisting of 22% thymine. Use Chargaff’s rules to fill in the percentages for the other three nitrogenous bases.

A DNA strand has 22% thymine. The percentages for adenine, guanine, and cytosine are blank.

50.

In considering the structure of the DNA double helix, how would you expect the structure to differ if there was base pairing between two purines? Between two pyrimidines?

51.

Identify the location of mRNA, rRNA, and tRNA in the figure.

A long strand is labeled ii. A small oval is attached to the bottom of this strand; and a large dome to the top. These two structures together are labeled iii. Smaller rectangles sit inside the large dome and are attached to small segments of the long strand. These rectangles are labeled i.

52.

Why does it make sense that tRNA and rRNA molecules are more stable than mRNA molecules?

53.

A new type of bacteriophage has been isolated and you are in charge of characterizing its genome. The base composition of the bacteriophage is A (15%), C (20%), T (35%), and G (30%). What can you conclude about the genome of the virus?