Microbiology and Immunology

WORLD OF MICROBIOLOGY AND IMMUNOLOGY Cell cycle (eukaryotic), genetic regulation of

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trioles’ migration to opposite cell poles. During metaphase the

chromosomes organize at the equator of a spindle apparatus

(microtubules), forming a structure termed metaphase plate.

The sister-chromatids are separated and joined to different

centromeres, while the microtubules forming the spindle are

attached to a region of the centromere termed kinetochore.

During anaphase there are spindles, running from each oppo-

site kinetochore, that pull each set of chromosomes to their

respective cell poles, thus ensuring that in the following phase

each new cell will ultimately receive an equal division of chro-

mosomes. During telophase, kinetochores and spindles disin-

tegrate, the reorganization of nucleus begins, chromatin

becomes less condensed, and the nucleus membrane start

forming again around each set of chromosomes. The

cytoskeleton is reorganized and the somatic cell has now dou-

bled its volume and presents two organized nucleus.

Cytokinesis usually begins during telophase, and is the

process of cytoplasmatic division. This process of division

Scanning electron micrograph of eukaryotic cell division.

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