Pancreatic cells, which secrete a large amount of digestive enzymes, are labeled with radioactive leucine and then chased for several hours with nonradioactive leucine. Photographic emulsions are prepared at different times during the chase. Where would the black spots appear on an emulsion prepared 3 hours after the pulse?
A. Golgi apparatus
B. Secretory vesicles
C. Exterior of the cell
D. Rough ER

Option-C

Explanation:

A pulse-chase experiment which is used to study the cellular process taking place in the cells. This uses the labelled molecule which is incorporated into the cellular pathway and then the unlabeled molecules are used over time to determine how much time is required by the unlabeled molecule to replace the labelled molecule.

In the given question, the pancreatic cell which secretes the digestive enzyme known as the acinar cell is labelled with the leucine and then used unlabeled leucine.

When observed after three hours, the black spots will appear on the exterior of the cell as the protein has been synthesised by the ER and now has been secreted from the cell.

Thus, Option-C is the correct answer.

the answer is tropical areas. the tropical areas obtain more

radiant energy from the sun than they lose to space through terrestrial

radiation, and vice versa for polar areas. earth has an energy remaining in the

tropics and an energy scarcity for the polar areas.

explanation:

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.