Biology On multicellular eukaryotes there are two types of cell division, mitotic consist of mitosis and cytokinesis and meiosis, the major use of mitosis is for division at autonomous cell, meiosis is for division at reproduction cell.
This type of division is restricted to only the sex organs. In plants meiosis occurs in the flowers in the anthers male meiosis and in the ovary females' meiosis and in animals such divisions occur in male and female gonads. Meiosis is relatively long sometimes very Short essay on meiosis and complex where single diploid 2n cells are reduced to form haploid n cells or gametes.
For example, if the somatic cells of Alliums cape have 16 chromosomes in the nucleus, the meiotic products shall have 4 cells with 8 chromosomes in each.
All the sexually reproducing plants and animals have this type of cell division to produce gametes. The gametes of opposite sex male and female unite to produce a zygotic cell, which forms the first cell of a sporophyte.
A plant or an animal has a fixed number of chromosomes in its nucleus and this number is maintained for generations through the process of meiosis, which reduce the number of chromosomes of the uniting gametes to half before their union. The process of meiosis is completed through two major phase's viz.
Meiosis - I and Meiosis-II. Meiosis-I consumes a lot of time and major events occur in this phase. This has been divided into prophase-I, metaphase-I, anaphase-I and telophase-I with prophase-I taking the longest duration among them.
This rather elaborate pro-phase- I is sub-divided for convenience to Leptotene, Zygotene, Pachytene, Diplotene and Diakinesis, based on the appearance of chromosomes during the progress of meiosis. Each of the sub-stages has characteristic features of chromosomes, which are normally clearly visible under microscope.
Prophase-I is quickly followed by metaphase, anaphase and telophase in succession to wind up the process of Meiosis-I resulting in two cells. After a short gap, the cells enter the second phase of division, the Meiosis-II that is more or less similar to mitosis.
The end result is formation of 4 haploid cells from every meiocyte. Like mitosis meiosis -I is initiated only after S phase where the parental chromosomes are replicated to produce identical sister chromatids.
But the pattern of chromosome segregation in meiosis-I is dramatically different from that in mitosis. The sequence is as follows: Leptotene "Thin thread" This is marked by an increase in nuclear volume. The chromosomes start to appear clearly as a result of condensation and coiling of chromatin fibers.
The appearance of chromosomes here are like thin threads and hence the name.Mitosis and Meiosis Essay BIO Meiosis, on the other hand, is a process of taking a diploid cell (a cell with the full number of chromosomes) and producing haploid gametes (cells with only half the number of chromosomes).
In plants meiosis occurs in the flowers in the anthers (male meiosis) and in the ovary (females' meiosis) and in animals such divisions Short Essay on Meiosis of . Cell Division Mitosis And Meiosis Biology Essay. Print Reference cytokinesis is delayed until after meiosis II. Also, a short interphase II may begin.
No replication of chromosomes occurs during this period. If you are the original writer of this essay and no longer wish to have the essay published on the UK Essays website then please. Comparing Mitosis and Meiosis Essay - Comparing Mitosis and Meiosis with reference to i.
Chromosomesii. Biological significance i. are generally nonvascular and very short in height, Pterophytes (ferns) are vascular plants that usually grow much taller than mosses.
While the dominant generation in mosses is the gametophyte, ferns exhibit. Cell Division Mitosis And Meiosis Biology Essay.
Print Reference this This is not an example of the work written by our professional essay writers. You can view samples of our cytokinesis is delayed until after meiosis II. Also, a short interphase II may begin. No replication of chromosomes occurs during this period.
Instead, part II of. Get an answer for 'In ONE short paragraph, write a brief introduction to 'meiosis'?' and find homework help for other Science questions at eNotes.