Cell Cycle and Cell Division Test - 2

The plants can show mitotic divisions in both haploid and diploid cells due to alternation of generations in life cycle.

All the phases of cell cycle in mammalian cell are completed in 24 hours.

S phase marks the period during which DNA synthesis or replication takes place. During this time the amount of DNA per cell doubles. If the initial amount of DNA is denoted as 2C then it increases to 4C.and even in anaphase the chromosome numbers are changed.

Yeast can progress through the cell cycle in only about 90 minutes due to its simple organisation.

The M Phase represents the phase when the actual cell division or mitosis occurs/starts during cell cycle.

Onion root tip cells have 16 chromosomes in each cell, same as the number of chromosomes in somatic cells.

During the G2 phase, proteins and RNA are synthesised in preparation for mitosis while cell growth continues.

The interphase, though called the resting phase, is the time during which the cell is preparing for division by undergoing  cell growth  in an orderly manner. No divisional activities occur during this phase. Hence the name.

In animals, mitotic cell division is only seen in the diploid somatic cell since mitosis produces cells with same number of chromosomes as that of parents.

In Go stage the cells are in a metabolically active state but do not divide unless there are some abnormal genes which reverses the same. This stage is also called quiscent stage. Examples human nerve cells.