Tag: structure of chromosome, cell cycle and cell division

All the different cells of our body usually live, grow and divide in harmony. Our body has many different signals that control how much, and how often our cells divide. If any of these signals are faulty or missing, the result can be cancer, where too many cells are produced.

The major events that take place in mitosis are the alignment of chromosomes at the center of the cell and the subsequent separation of sister chromatids to opposite mitotic spindle poles. Those occur in metaphase and anaphase respectively.

At G1 phase, there will be 14 chromosomes as no DNA replication has taken place. After S Phase, the DNA content doubles but chromosome number still remains same here 14. After completion of M phase, the number of chromosomes will be 28 with each daughter cell having same number of chromosomes as that of parent i.e 14

$G _2$ phase is the phase of cell cycle occurs immediately prior to mitosis.
sequence of cell cycle is -- $G _1$ to $S$ to $G _2$ to $M$ to cytokinesis.

In binary fission, parent cell divides into two equal halves called daughter cells. Daughter cells are identical to each other and to their parent cell. Organisms like the amoeba, bacteria, euglena, etc. exhibit binary fission. During multiple fission, the organism divides itself into numerous daughter cells.