Mitosis and Meiosis

[grayfalcon89]

This is sort of stupid questions that I learned this before but I can't remember now. What is exactly difference between the mitosis and meiosis?

 

I know that the mitosis is the division of the two nuclei but when I got to the part of the chromatin, I got lost. What is the DNA double helix and how this differ from chromosome itself?

 

Also, from the cell cycle, I see the word interphase. There are three part, G_1, S, and G_2.

 

What is the difference between each step?

 

Appreciated greatly. Happy New Year!

[5614]

http://www.bbc.co.uk/schools/gcsebitesize/biology/cellprocesses/celldivisionrev4.shtml

 

is a good site for learning it and revising it... any questions, ask here.

[PuelloDiablo]

This is sort of stupid questions that I learned this before but I can't remember now. What is exactly difference between the mitosis and meiosis?

 

I know that the mitosis is the division of the two nuclei but when I got to the part of the chromatin' date=' I got lost. What is the DNA double helix and how this differ from chromosome itself?

 

Also, from the cell cycle, I see the word interphase. There are three part, G_1, S, and G_2.

 

What is the difference between each step?

 

Appreciated greatly. Happy New Year! [/quote']

 

Check you textbook, it would probable that there would be a few chapters covering cell division....

[UCF-Forensic]

easy way to remember it. Mitosis is cell cloning. It happens in all autosomes. Meiosis only happens in sex cells. Meiosis imparts diversity because it results in 4 genetically different daughter cells.

 

Just thought I'de sound smart!

 

~Steve

[OnlySinan]

I think this question is better to answer if you look in a school text-book. But below are some short answers!

 

>>>I know that the mitosis is the division of the two nuclei but when I got to the part of the chromatin, I got lost.

Mitosis is the cel-cycle phase before the cytokynesis (nucleus division). It includes DNA duplication (2 times the DNA amount) and DNA condensation (when visible chromosomes are made), etc....

After mitosis is finished, two cells are generated with exactly the same DNA (n=2).

 

Meiosis is almost the same as mitosis but it it generates two cells without duplicating the DNA. The two cells have the half of the normal DNA amount. As usual: sperm cells and egg cells are generated via meiosis because they must have that half amount of the DNA of a normal cell (haploid; n=1).

 

>>>What is the DNA double helix and how this differ from chromosome itself?

DNA double helix is the DNA made out of 2 phosphodiesther backbones with bases opposing each other. A chromosome is a long linked DNA molecule containing many genes. During mitosis the chromosomes condense and become visible.

 

>>>Also, from the cell cycle, I see the word interphase. There are three part, G_1, S, and G_2. What is the difference between each step?

G1: first gap phase where the cell checks if the internal and external environment capable is for starting the S phase.

S: the phase where the DNA duplicates.

G2: The cell checks if it's appropriate to go into mitosis again.

 

Cheerz! Sinan

[neo007]

Following on from OnlySinan...

Mitosis involves the production of new cells through cell division, where the daughter cells are exactly the same as the parent cell. Humans have a diploid number of chromosomes (23 pairs), ie 46 chromosomes, during mitosis this diploid number is consistent in the daughter cells through mitosis, however in meiosis the haploid number is halved, therefore the chromosome number is halved to 23.