Unit 11: Genetics and Genetic Engineering
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Cell Division
Mitosis is a mechanism that only occurs in the skin, DNA, muscles, and respiratory
system. In this process, cells will divide one time to produce two daughter cells
(Charlotte B. 2016). The daughter cells will have the same number of chromosomes as
the parent nucleus.
This process of mitosis involves five stages:
1. Interphase
The Deoxyribonucleic Acid (DNA) in the cell is duplicated, forming two full
indistinguishable sets of chromosomes.
In the exterior of the nucleus are two organelles known as centrosomes, each
holding a centriole in their structure. These centrioles aid in the formation of
spindle fibers, that will separate the chromosomes during cell division (Chantelle
D. 2019).
Hollow cylinders recognised as microtubules will gradually start to extend from the
centrioles during interphase.
2. Prophase
The duplicated chromosomes will compress to become X-shaped, and they then
arrange themselves into pairs.
Each individual chromosome comprises two sister chromatids (a dyad) that each
contains proportionate genetic information (DNA).
As the homologous chromosomes are paired up, they interchange fragments of
deoxyribonucleic acid between each other.
The microtubules, along with other proteins create a meiotic spindle, that engulfs
the chromosomes, forming a circle around it.
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