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MITOSIS, MEIOSIS, AND CELL DIVISION

Although all parts of the cell cycle are extremely important (interphase for cellular growth and replication of cell and nuclear structures), (cytokinesis for the division of the cell, its cytoplasm, its new structures and the daughter chromosomes), Mitosis and Meiosis are the very similar processes that I found most difficult to understand well, and they are also the most involved part of cell division. With this in mind, I will take a closer look at mitosis and meiosis below. Let's begin by watching these excellent short videoes, the first that focuses specificallly on mitosis, and the second on meiosis.

Marsh, K., 2010.

Pigsahscience , 2009.

Garlandscience, 2009.

Hopefully, the above movies gave you a good idea about how mitosis and meiosis happen, and what takes places. I've put a picture here beside the text comparing the 2, just to make sure the differences are understood. Mitosis is the regular cell division that starts with one complete cell and ends with 2 complete cells, all having 2 copies of each chromosome (one from each parent). These are called diploid cells, and do all the growing, repair and maintenance work for your body.
Meiosis produces haploid cells, which contain one of each chromosome that is need for normal growth. Haploid cells are made by two cytokinesis, or cell division. At the first division, homologous pairs (one set from mom and one set from dad), line up together, so that when the division is open, each of the 2 new cells has the same number and match in chromosomes. Then these cells go through the growth cycle once again, this time separating in to 4 separate cells with half the number of chromosomes. These haploid cells are sperm or egg and two must come together (one from the mom and one from the dad) to make a complete cell that becomes an embryo and then a living eukaryote.

continue for cool links and references...

Accessexcellence.org., 2006.