Answer:
The effect of an external physical factor on cell division is clearly seen in density-dependent inhibition, a phenomenon in which crowded cells stop dividing. ... When cells have formed a complete single layer, they stop dividing (density-dependent inhibition).
Explanation:
Answer;
Cell membrane
A cell membrane acts as a boundary that separates things that are inside the system from those that are outside the system.
Explanation;
It is a thin semipermeable structure that surrounds the cytoplasm of a cell.
The membrane functions to protect the integrity of the internal environment of the cell by allowing selective movements of materials in and out of the cell.
The membrane consists of a phospholipid bilayer with proteins embedded in it.
d. Eras are divided into periods; periods are divided into epochs.
The geologic time is divided from the largest defined unit of time called supereon, which is composed of eons. Eons are further subdivided into eras, periods, epochs and the smallest unit of time - ages.
