What is the differences between mitosis and meiosis?

Question

I have some clues about it, but not exactly sure.
During mitosis, a parent cell divides into two exactly the same daughter cells, right?
During meisosis, it reduces the chromosome number in half, but the daughter cells are not the same. But why isnt the daughter cells the same?
Since my bio class start with plants, i am unclear on this mitosis and meiosis stuff (and i try to read the chapter about mitosis and meiosis, but got so confused about it...).

Answer 1

Mitosis occurs and the daughter cells are the same as the parent cells. It contains a DIPLOID number of chromosomes.

Meiosis is for the formation of gametes. As the chromosomes arrange at the center of the cell and is ready to split, the chromosomes exchange some genetic material. When they do split, it results in variation between the chromosomes due to the exchange of genetic material. It would then further split and result in a HAPLOID number of chromosomes.

*diploid (2n) = twice the number of chromosomes in gametes of that organism
*haploid (n) = number of chromosomes in gametes of that organism
*gametes = ovum, sperm (animals) / pollen grains, ovum (plants)

Answer 2

Most organisms are what are referred to as diploid. Ploidy refers to the basic set of chromosomes in a cell. Diploid means that the cells have a two (di) complements of matching DNA. One set of the DNA comes from the mother and one from the father.

Your body and the body of most other organisms contain many diploid cells with exactly the same DNA. Each time a cell divides, the DNA must completely replicate. You are correct that during mitosis, the DNA replicates and divides to form identical strands of DNA (chromosomes) that separate into the newly formed cells (which are identical). It is an amazing process, when you consider that each of your cells contains DNA composed of 3 billion base pairs (everytime a cell divides these base pairs are replicated!!). Just think how many cell divisions were required to form your little ole body.

Now consider that during sexual reproduction DNA from the father and mother must join to form the fertilized egg that develops into the mature organism. If the DNA from each parent were simply mixed together, then the DNA content in each cell would double (diploid to 4 sets or tetraploid). The next generation would then double again (octaploidy). You can see that this would be problematical. Genes would be duplicated and the nucleus would have to keep expanding, as would the cells. BTW, gene duplication in and of itself is not necessarily a bad thing (see below).

Sooo, it is important that germ cells (the cells for reproduction) have half the amount of DNA than that which is found in the rest of the organism (the so-called somatic cells). This is where meiosis plays an important role. It decreases the ploidy by one-half.

What may be the confusing part of this is that during meiosis there are two divisions. During the first division the DNA is replicated and the cells divide, to produce 2 diploid cells (as in mitosis). During the next stage the DNA is not replicated, but the two new cells divide again. The result is 4 cells that are haploid (single set of DNA). Again, the amazing part of this is that the DNA divides evenly and correctly almost every time.

OK, so now there are these haploid cells or germ cells with half the amount of DNA as the somatic cells. You can see this is great, because now a germ cell from the mother (egg) and a germ cell from the father (sperm) can combine to make a new diploid cell (zygote, a fertilized egg) that develops into a new organism!!!

You will learn that during meiosis a process called crossing over can occur. The process "shuffles" the DNA, so each germ cell won't be identical, so that is one of the reasons brothers and sisters aren't exactly the same. Note also that identical twins aren't really "identical" either, but their DNA is essentially identical.

Interestingly, the part of your biology class on plants failed to point out that many plants are polyploid (they actually are tetraploid and even more in some cases).

I don't know why starting with plants affects your understanding of mitosis and meiosis. The processes are exactly the same, but plant cells don't have centrioles.

Now go study!!! The more you learn, the more fun you will have.

Answer 3

In mitosis, 2 daughter cells are produced from 1 parent cell. These 2 daughter cells are also diploid in chromosome number. However, in meiosis, 4 haploid daughter cells are formed from 1 parent cell. These 4 cells are formed after 2 cycles of meiosis-Meiosis 1 and meiosis 2.

Answer 4

Mitosis is a cell making an exact copy of itself. Meiosis is the process by which eggs and sperm are made for the purpose of genetic recombination. In meiosis, each egg or sperm contains only a fraction of the chromosomes necessary to support life- so when the sperm and egg get together during conception, they both contribute to the genetic information that will passed on to the embrio. hope this helps

Answer 5

mitosis is where you take one cell and copy and divide to make 2 whole daughter cells.

meiosis is where you make gametes. You start with one cell, make 2 whole daughter cells (like mitosis) then those 2 daughter cells divide in half to make 4 cells with only half the number of chromosomes

Answer 6

You are correct about mitosis. Meiosis separates the male Y chromosomes & the female X's. This is why they are different. They require the opposite sex's gamete to complete the entire genome.

Answer 7

miitosis - it is the process of cell division which takes place in the body to increase the number of cells for growth. it results in the production of identical cells. it is because the same cells divide themselves to grow in number. this process helps in growth of a particular cell type. all different cell types keep growing.

meiosis - it is the process of cell division which takes place in the reproductive organs like testis, ovary and anther. it helps in the formation of sperms and ova. it results in the formation of cells having half the number of chromosomes. the daughter cells are not the same because the cells have to develop into different organs.

Answer 8

In Mitosis it diffuses
In meosis it breaks