Cleavage stages of the cell.

Cleavage stages of the cell.

Gene is the elementary unit of the properties are derived in all chromosomes. In fish and other Vertebrate, each chromosome known to contain hundreds or even thousands of genes. Gene as the smallest unit, the host of the nature of the kromonemata descendants of the core parts of the chromosome.

At the time of cell division, chromosomes are divided but joined this division depends on the kind of pembelahannya.

Cell division there are two kinds, namely mitotic division and meiosis. Found in mitotic somatic cells, where the division is the number of chromosomes there is no change that is still 2n or diploid. While on the meiotic division in gamete formation of chromosome number is reduced by half or n (haploid) (Fig. 18).

According to the processes that occur during cleavage, can be classified into stages, as follows:

Prophase : In the core there is a formation of a complex structure that looks like yarn. At the beginning of this stage were two kronemata but ultimately lost or kronemata is not visible.

Metaphase : Chromosomes line up at the cell equator.

Anaphase : Chromosomes split lengthwise into two parts. Each containing one kromonemata. Then each part of the chromosome that has been cut to move toward one pole of the cell and ultimately in a single cell to form two sets of chromosomes as the porphase stage.

Telophase : Each chromosome is returned to the metabolic condition. Re-formed the core wall surrounding the new core. Eventually formed two identical daughter cells with stem cells.

source: M. Ichsan Effendie, 1997

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