In prophase, the spindle fibers appear and the chromosomes begin to condense into compact structures. Each chromosome has two chromatids that are held together by the centromere. It is the longest phase in Mitosis as it occupies almost half of it. This phase is related to another phase called prometaphase which is an intermediate between prophase and metaphase where the spindle fibers attach to the chromosomes as they begin to align themselves on the mid-line axis called metaphase plate. Spindle fibers bind to kinetochore regions.
In metaphase, the chromosomes finish aligning themselves on the metaphase plase.
In anaphase, the centromeres begin to divide by pulling the sister chromatids apart as they move to the opposite ends of the cells. They are capable of doing that because of the spindle fibers that are bound to the kinetochore regions. Daughter chromosomes (separated sister chromitds) are now available.
Finally, in the final stage of mitosis which is the telophase, the chromosomes uncoil, the spindle fibers disappear and the nuclear membrane is formed around the chromosomes.
QUESTIONS:
1) What is the function of centriole?
2) After which stage does the cytlokinesis occur?
REFERENCES
Britannica. (2014). Cell cycle. Retrieved February 22, 2019, from https://www.britannica.com/science/cell-cycle
To answer your second question:
ReplyDelete- Cytlokinesis occurs after mitosis
Answering your first question, there are two main functions for a centriole; The main function of the centriole is to help with cell division in animal cells, and the second function is Celiogenesis. It is simply the formation of cilia and flagella on the surface of cells. Cilia and flagella help the cell move.
ReplyDeleteTo answer your first question: These structures play and important role in the attachment and orientation of microtubules.
ReplyDeleteDr. Hatoum thank you for this blog, I have become exposed to so many new ways of approaching biology and possibly teaching it to my own children. I would've originally said that the centriole is the power house of the cell, but now I know that it is not. It functions to power mitosis.
ReplyDeletelegend
DeleteThe main function of the centriole is to help with cell division in animal cells. The centrioles help in the formation of the spindle fibers that separate the chromosomes during cell division (mitosis)
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ReplyDeleteAnswer to question 1: The centriole is an organelle in the cell which plays a necessary and essential role in cell division (mitosis).
ReplyDeleteAnswer to question 2: Cytokinesis occurs after telophase of mitosis.