Question

Radioactive amino acids incorporated into the proteins were rejected into the retina of a rabbit. After measuring the radioactivity and distance after a couple of experiments, two moving peaks were observed. The first peak moved 0.5-2 mm/day indicating that those are _________________ proteins which took up the radioactive AA whereas the second peak moved 200-400 mm/day indicating that those are _________________ proteins which took up the radioactive AA.
a. cytoplasmic, transmembrane
b. secreted, transmembrane
c. transmembrane, cytoplasmic

Answer 1

Answer:

cytoplasmic, transmembrane

Explanation:

Pulse chase experiment is an important technique used to analyze the cellular process by labeling the cells with radioactive compound.

The radioactive amino acids is injected into the rabbit's retina. Two different moving peaks are observed during the experiment.  The first peak moved at 0.5-2 mm/day and second peak at 200-400 mm/day. These peaks are observed due to difference in the synthesis and transport rate of the protein. Cytoplasmic protein has slow transport and sorting rate, indicates the first peak. The second peak corresponds to transmembrane protein.

Thus, the correct answer is option (a).