Cells usually stop dividing after certain number of divisions. In malignant or cancerous cells this automatic stoppage of cell division does not work. As a result ma+gnant cells keep on dividing endlessly causing the cancerous growth

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Telophase is the fifth and final phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells.

Prophase - the first stage of mitosis. Spindles attached to kinetochores begin to shorten. This exerts a force on the sister chromatids that pulls them apart. Spindle fibers continue to shorten, pulling chromatids to opposite poles.

no variations from the normal (2n = 48) diploid chromosome number. this somatic human tissue. it is known that the cestrus cycle takes about 4days. In both species periods of mitotic activity have been found during the normal develop- ment of the endometrium.

Androecium, Gynoecium.

The chiasmata formation is the indication of completion of crossing over and beginning of separation of chromosomes. The chiasmata formed when the chromosomal parts begin to repel each other except in the region where these are in contact. Thus, chiasmata formation is necessary for the separation of homologous chromosomes.

The complex formed by a pair of synapsed homologous chromosomes is called a bivalent or a tetrad. It consists of four chromatids.

Mitosis is divided into 4 stages which are prophase, metaphase, anaphase and telophase in order.

Colchicine is considered to be the mitotic poison because
(i) This alkaloid inhibits the formation of spindle by preventing assembly of microtubules. It is an alkaloid obtained from the corms of Autumn crocus.
(ii) The chromosomes duplicate, but they remain within the same cell, increasing the number of chromosomes. As a result, the colchicine treated meristematic cells show doubling of chromosome.

Mitosis is called an equational division because it divides the mother cell into two daughter cell, which are identical to the original mother cell in every respect. In mitosis, the chromosomes of the mother cell are duplicated and distributed equally to the daughter cells and daughter cells have same number of chromosomes as matter cell has.

Differences between metaphase of mitosis and metaphase-I of meiosis are

It is the equatorial plane at the centre of cell on which chromosomes arrange during metaphase.

It happens so because it is physically easier for short and compact chromosomes to move through the cytoplasm than the very long twisted interphase chromosomes.

G_o is the quiescent stage of the cell cycle. Also known as inactive stage of the cell cycle. Cells in this stage remain metabolically active, but no longer proliferate unless they do not get instruction to do so, depending on the requirement of the organisms.