Mitosis in Onion Root Tips Free essay! Download now
Home > A Level > Biology > Mitosis in Onion Root Tips
Mitosis in Onion Root Tips
You can download this essay for free. All you need to do is register and submit at least one of your essays to us.
Or you can purchase this essay for just $2 instantly without registering
Downloads to date:
| Words: 1101 | Submitted: 28-Mar-2011
96.5% | Number of pages: 6 | Filetype: Word .doc
This is what the first 3 pages of the essay look like
DescriptionMitosis in Onion Root Tips. Objectives: You will fix, stain, and make slides of onion root tips. These slides will be studied for the presence of cells in the four stages of mitosis.
Mitosis in Onion Root Tips (Lab)
You will fix, stain, and make slides of onion root tips. These slides will be studied for the presence of cells in the four stages of mitosis.
At the completion of this laboratory you should be able to
Stain tissue for the identification of cells in the various stages of mitosis
Identify the stages of mitosis in plant cells
All new cells come from previously existing cells. New cells are formed by the process of cell division which involves both replication of the cellís nucleus (karyokinesis) and division of the cytoplasm (cytokinesis) to form two genetically identical daughter cells. There are two types of nuclear division: mitosis and meiosis. Mitosis typically results in new somatic (body) cells. Formation of an adult organism from a fertilized egg, asexual reproduction, regeneration,and maintenance or repair of body parts is accomplished through mitotic cell division. Meiosis, on the other hand, results in the formation of either gametes (in animals) or spores (in plants). These cells have half the chromosome number of the parent cell.
Where does one find cells in the process of mitosis? Plants and animals differ in this respect. In higher plants the process of forming new cells is restricted to special growth regions called meristems. These regions usually occur at the tips of stems or roots. In animals, cell division occurs almost anywhere as new cells are formed or as new cells replace old ones. In both plants and animals, though, tissues rarely divide once the organism is mature.
To study the stages of mitosis, you need to look for tissues where there are many cells in the process of mitosis. In plants, this restricts your search to growing tips, such as the onion root tip.
The phases of plant mitosis are:
The nondividing cell is in a stage called interphase. The nucleus may have one or more dark-stained nucleoli and is filled with a fine network of threads, the chromatin. Interphase is essential to cell division because the genetic material (DNA) is duplicated (replicated) during this stage.
The first sign of a division is prophase, in which a thickening of the chromatin threads occurs. Thickening continues until it is evident that the chromatin has condensed into chromosomes. With somewhat higher magnification you may be able to see that each chromosome is composed of two chromatids. As prophase continues, the chromatids continue to shorten and thicken. In late prophase the ...
Download this essay in full now!
Just upload at one of your essays to our database and instantly download your selection! Registration takes seconds
Comments and reviews
Reviews are written by members who have downloaded the essay
No comments yet. If you download the essay you can review it afterwards.