Reproductive isolation but more specifically I think it would be geographic isolation
The Muscles, the shrimp stores energy in it's muscles.
Crude density and ecological density are both related but different. Ecological density is the portion of land that a certain species can colonize, where as crude density is the land within the organism's range.
The answer is mitochondrion. Mitochondria are critical for the cell’s biochemical processes that require energy to be powered. Mitochondria are responsible for generating this power in the form of ATP through a process called chemiosmosis. Without ATP, the cell would immediately die since it would be incapable of performing virtually all biochemical processes that re required to sustain life.
I think it might have been the elephant, which is letter b
