UGH! Science help needed! Mitosis v. Meiosis. I don't get this!

[Hoggirl]

Can someone please explain this to me in a language I can understand. English would be nice! I am so un-science-y! I have looked on-line and there are lots of cute little moving diagrams of chromosomes (sp?) lining up and dividing, etc. but I am NOT getting this. Isn't one sexual and one asexual? Do certain kinds of cells divide one way and certain kinds of cells divide the other??? Help, help, help! See? How in the world am I EVER going to be able to teach "BIG" science! Ack!!
Cynthia

[Tarheel Heather]

mitosis is when BODY cells reproduce, and meiosis is when SEX cells reproduce.

Pretty much the nitty gritty.


Mitosis: duplication of the chromosomes. in order to separate and multiply.
(from Wikipedia: Mitosis is the process by which a cell duplicates the chromosomes in its cell nucleus, in order to generate two, identical, daughter nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two daughter cells containing roughly equal shares of these cellular components. Mitosis and cytokinesis together define the mitotic (M) phase of the cell cycle, the division of the mother cell into two daughter cells, each with the genetic equivalent of the parent cell.)
Meiosis: where the cell splits, and needs another cell from the opposite sex to make it whole again.
(this is our method of reproductrion!)
(from wikipedia:In biology, meiosis (pronounced my-oh-sis) is the process by which one diploid eukaryotic cell divides to generate four haploid cells often called gametes. The word "meiosis" comes from the Greek meioun, meaning "to make smaller," since it results in a reduction in chromosome number in the gamete cell.)

[FloridaLisa]

Mitosis is asexual reproduction, growing and healing. Mitosis will always result in the reproduction of identical cells. Think a bacteria multiplying or lizard regrowing it's tail.

Meiosis is sexual reproduction. Meiosis will always produce a different daughter cell than the parent cell because it takes another two different organisms. Think of a flower pollination or um, sexual reproduction.

It can be confusing. I always thin of a silly mnemonic to help me remember which is which.

HTH,
Lisa

[Kissy]

Here is an interactive site that shows both.

http://www.cellsalive.com/meiosis.htm

[Alana in Canada]

What's the mnemonic?, FloridaLisa?

[Hoggirl]

nt

[Karin]

However, meiosis has 2 steps, one of which is like mitosis. Just to confuse things!

[Mom to 3 Island Boys]

The way I usually explain it that seems to "stick" with the most people is that mitosis produces body cells while meiosis produces sex cells.

In Mitosis, the initial cell doubles everything and then divides to produce 2 "daughter" cells. These will be "body" cells (somatic for the science minded) ~ they are genetically identical to the initial cell. It's how our bodies make more cells when we grow or repair.

In Meiosis, the initial cell ends up dividing twice ~ into four daughter cells. These will be "sex" cells (gametes for the science minded). Each cell will only have half of the genes from the parent cell. These cells are produced for sexual reproduction. They are made to eventually meet up with another "sex" cell to become a "whole" cell ~ sperm and egg coming together.

This is pretty much what others have said, but I know that this can be difficult to understand for many people so I thought I'd throw in my explanation! (Probably not even 2 cents worth this late in the conversation! :))