Q. 34 - Biology

Question

List some reasons why a cell that has just completed cytokinesis might enter the G0 phase instead of the G1 phase.

Step-by-Step Solution

Answer

Cells like nerve cells and cardiac cells enter G0 phase permanently as they attain their maturity. But oocytes enter the G0 phase temporarily and again start to function after puberty. The reason of entering G0 phases are some environmental conditions such as  nutrients inavailability, or absence of growth factors etc. 

Step 1: Given information

G0 phase is one of the phase of cell cycle where neither the cell shows division nor it prepares for any growth and maturity. In simplest term, we can describe this phase as a quiescent (inactive) stage. 

Step 2: Explanation

Some cells enter G0 temporarily due to unfavorable environmental conditions such as lack of nutrients, lack of growth factor stimulations. The cell will remain in this phase until conditions becomes favorable or until some external signal comes forward. Example- oocytes enter the G0 phase and becomes active again after puberty. 

Some other cells such as mature cardiac muscle and nerve cells, never or rarely divide further, hence, they remain in G0 permanently.