Why is a control system for mitosis for animals and plant’s necessary?

to avoid constant cell division when necessary and when not

Explanation:

Control of the cell cycle is needed for various reasons. If the cell cycle were not regulated/controlled, cells could constantly undergo cell division over and over. While this may be beneficial to some cells (which includes cancer cells as this stage of continuous division is a favourable condition for the cells leading to the promotion of cancer (carcinogenesis)), apart from this, reproduction without cause would be biologically wasteful.

Internal regulation of the cell cycle is also important to indicate movement from one phase to the next at proper times. This regulation is not based on thorough time restriction, but rather with feedback from the cell.

Extreme regulation of this process make certain that a dividing cell's DNA is  properly copied, any errors in the DNA are repaired by the repair system after a feedback mechanism, and each daughter cell receives a full set of chromosomes. This is achieved through checkpoints in each phase of the cell cycle. Two groups of proteins, called cyclins and cyclin-dependent kinases (Cdks), are involved in the progress of the cell as it undergoes this cycle through the various checkpoints there are.

g1

choices:

a. g2. b. g1. c. m

cell division has two checkpoints namely, g1

checkpoint and spindle assembly checkpoint. the checkpoint which determines if

division has properly occurred is the g1 checkpoint. at this point, is a damage

in the dna is detected or  the has not reach the optimum size, the cell is

stopped in g1 and is not allowed to proceed to further process.

source:

a time line cause it goes from 685 to 978