Question

In: Biology

Meiosis is a process by which a single cell divides into 4 daughter cells. The purpose...

Meiosis is a process by which a single cell divides into 4 daughter cells. The purpose of meiosis is only to produce gametes (sex cells). In the process of spermatogenesis all 4 of the daughter cells are equal, but in the process of oogenesis only one of the cells becomes an egg. The other 3 cells are polar bodies and they disintegrate. Meiosis has 2 separate divisions and this allows for the reduction in the number of chromosomes. Meiosis occurs only in sexually reproducing organisms.

The other form of cell division that takes place in humans is called mitosis and it results in 2 cells that are identical to the original cell. The purpose of mitosis is growth and repair.

Why is it necessary to reduce the number of chromosomes in gametes?

Solutions

Expert Solution

Meiosis is areduction divison that is necessary in sexually reproducing organisms to maintain the species number of chromosomes. gametes, or sex cells must have half the chromosomes that the parent cell has. at fertilizatio, two gametes fuse together to form the offspring. if these gametes had the same number of chromosomes as the parent does, each generation would have double the chromosomes as the previous generation did. To, prevent that meiosis occurs in gonads - ovaries or testes. If the ovary or test cell is diploid(2n) , the gametes or sex cells - sperm and egg will be haploid (n) after meiosis occurs. For example, if a human teste or ovary cell has 46 chromosome , replication occurs. The result will be 46 pairs or 92 chromosomes. MEiosis has two round of cell division - meiosis 1 and 2. After meiosis 1, takes place two daughter cells, each with 46 chromosomes are the result. After meiosis 2, each of these daughter cells divide and 4 diploid cells are result. In this example, they will each have 23 chromosomes or the haploid amount. These can be used as gametes, sperm or egg cells during sexual reproduction. In the case of males , all 4 haploid cells will develop into sperm. In the case of females, only one becomes the ova or egg, and other 3 cells are polar bodies.


Related Solutions

A germ cell divides to give rise to two daughter cells. Each of the two daughter...
A germ cell divides to give rise to two daughter cells. Each of the two daughter cells then divides to give rise to two daughter cells. Is the genetic information found in two daughter cells that arose from a cell that went through the second division, identical? Explain your answer.
1) During meiosis, an oocyte divides twice and generate 4 haploid cells. Cohesin proteins hold homologous...
1) During meiosis, an oocyte divides twice and generate 4 haploid cells. Cohesin proteins hold homologous chromosomes AND chromatids together. Experimental evidence shows these are loaded onto the chromosomes in S phase. Cohesin at the centromeres are released by securins during anaphase. SOme cohesin components such as SMC1 are down-regulated in older oocytes. If this is the case, at what stage(s) would you expect to see mis-segregating DNA? a. Meiosos I b. both meiosis I and II c. none of...
5B. at the end of meiosis II What is the significance of these daughter cells (i.e....
5B. at the end of meiosis II What is the significance of these daughter cells (i.e. what do they mature to become)? 6. Why is the reduction to haploid from diploid important in meiosis II?
Meiosis (what cells are produced by this process?): • Location of meiosis (where are gametes (eggs...
Meiosis (what cells are produced by this process?): • Location of meiosis (where are gametes (eggs and sperm) produced?) • How many cells are produced from meiosis? Are they haploid or diploid? Are they genetically unique or clones of the parent cell? • Know that crossing over between chromosomes and independent assortment of chromosomes are the source of genetically unique gametes and offspring.
As the chromosomes of a parent cell are duplicated and distributed to the two daughter cells during cell division
Changes in DNA structure during the cell cycle As the chromosomes of a parent cell are duplicated and distributed to the two daughter cells during cell division, the structure of the chromosomes changes. Answer the three questions for each phase of the cell cycle by dragging the yes and no labels to the appropriate locations in the table. Note: Assume that by the end of the M phase, the parent cell has not yet divided to form two daughter cells.
Explain (writedown) What is the general purpose of Mitosis vs Meiosis in normal cells?
Explain (writedown) What is the general purpose of Mitosis vs Meiosis in normal cells?
a. Compare the process of mitosis with the process of meiosis. Describe major cell cycle events....
a. Compare the process of mitosis with the process of meiosis. Describe major cell cycle events. (points: 4) What is significance of these two cell division types.
Starting with One Cell describe step by step the process of Meiosis I in males and...
Starting with One Cell describe step by step the process of Meiosis I in males and females (they have different end results). How many viable cells are there for the male and for the female at the end of Meiosis I?
The cell cycle represents the coordinated sequence of events in the life of a cell from its formation to its division into two daughter cells.
The cell cycle represents the coordinated sequence of events in the life of a cell from its formation to its division into two daughter cells. Most of the key events of the cell cycle are restricted to a specific time within the cycle. In this exercise, you will identify when various events occur during the cell cycle. Recall that interphase consists of the G1, S, and G2 subphases, and that the M phase consists of mitosis and cytokinesis. Drag each...
Why do cells have telomeres? Why do telomeres get shorter every time a cell divides? What...
Why do cells have telomeres? Why do telomeres get shorter every time a cell divides? What counteracts this shortening? What role do telomeres play in aging? If telomerase makes cancer cells immortal, could it prevent normal cells from aging? Do you think we could extend the average lifespan by preserving or restoring the length of telomeres with telomerase? If so, does that raise a risk the telomerase also will cause cancer?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT