Notes

Good day, everyone. My name is Renzel Mart C. Victolero from Grade 11, Section 3, St. Bruno. and Today, I will be discussing the process of mitosis and its importance.

What is mitosis?
Mitosis is a process of cell duplication, in which one cell divides into two genetically identical daughter cells. In the various stages of mitosis, the cell’s chromosomes are copied and then distributed equally between the two new nuclei of the daughter cells.

How does a cell prepare itself for Interphase?
Interphase is when the parent cell prepares itself for mitosis. This phase isn’t considered part of mitosis, but understanding what happens during interphase can help the steps of mitosis make a little more sense.

The G1 or Gap 1
Gap 1 or G1. During this stage, the cell performs its normal functions, and grows in size. The cell replicates organelles as necessary. As seen in the graphic above, cells can sometimes leave G1 and enter G0, or resting phase, as described above. If the cell is an actively dividing cell, it will continue interphase by entering the next phase synthesis.

S Phase or the Synthesis
The cell duplicates its DNA, ensuring each daughter cell will receive an identical set of chromosomes. The result is two identical sister chromatids for each chromosome where the centrosomes are also duplicated.

The G2 or Gap 2
After the DNA has been replicated during synthesis stage, the cell enters a second gap stage, known as Gap 2 or G2. During G2 the cell adds volume to the cytoplasm, and replicates many important organelles. In animals, the mitochondria are replicated to provide enough energy for the dividing cell. In plants, both the mitochondria and the chloroplasts must be replicated to provide the daughter cells with organelles capable of producing energy.
(My-oh-sis)
What's the difference of Mitosis to Meiosis? The answer is pretty simple!
Mitosis is the division of a cell into two daughter cells that are genetically identical to the parent cell. Meiosis is the division of a germ cell into four sex cells (e.g. egg or sperm), each with half the number of chromosomes of the parent cell. Mitosis is a means of asexual reproduction, whereas meiosis is necessary for sexual reproduction.

Now let's talk about the Phases of Mitosis.
The first phase is what we call the Prophase.
This is when the genetic fibers within the cell’s nucleus, known as chromatin, begin to condense and become tightly compacted together. It is also the condensing of chromosomes and separation of the centrioles in the centrosome. This organelle controls the microtubules in the cell, and each centriole is one half of the organelle. During prophase, they separate to provide microtubule centers in each new cell.

The second phase is the Metaphase
Metaphase is a stage in eukaryotic cell division in which the chromosomes align on the metaphase plate in the middle of the cell. Metaphase begins once all the kinetochore microtubules get attached to the sister chromatids’ centromeres during prometaphase.

The Third Phase is called Anaphase
Anaphase is a stage during eukaryotic cell division in which the chromosomes are segregated to opposite poles of the cell. This separation ensures that each new daughter cell will have an identical set of chromosomes.

The Last Phase is the Telophase
Telophase is the final stage in cell division. During telophase, the nuclear envelopes reform around the new nuclei in each half of the dividing cell. To understand it further, The separated chromosomes reach the opposite poles of the cell then a new nuclear membrane forms around each set of chromosomes, creating two separate nuclei. The chromosomes begin to decondense and return to their less condensed, stringy form.

But what is the purpose of mitosis on living organisms?
It provides us Growth, Genetic Stability, Replacement and regeneration of new cells, Asexual Reproduction,
Developmental Plasticity and Cell Differentiation, Genetic Consistency, Maintenance of Chromosome Number and many more.

Thank you very much for your time and attention in listening and joining me in discussing the process of mitosis. Until next time. Goodbye!