explain CELL DIVISION type
Cell division are of two types
1)Mitosis
2)Meiosis
Answers
CELL DIVISION
Cell division are of two types
Mitosis
Meiosis
1)Mitosis
Mitosis is a process where a single cell divides into two identical daughter cells (cell division).
During mitosis one cell? divides once to form two identical cells.
The major purpose of mitosis is for growth and to replace worn out cells.
If not corrected in time, mistakes made during mitosis can result in changes in the DNA? that can potentially lead to genetic disorders?.
Mitosis is divided into five phases:
1. Interphase:
The DNA in the cell is copied in preparation for cell division, this results in two identical full sets of chromosomes?.
Outside of the nucleus? are two centrosomes, each containing a pair of centrioles, these structures are critical for the process of cell division.
During interphase, microtubules extend from these centrosomes.
2. Prophase:
The chromosomes condense into X-shaped structures that can be easily seen under a microscope.
Each chromosome is composed of two sister chromatids, containing identical genetic information.
The chromosomes pair up so that both copies of chromosome 1 are together, both copies of chromosome 2 are together, and so on.
At the end of prophase the membrane around the nucleus in the cell dissolves away releasing the chromosomes.
The mitotic spindle, consisting of the microtubules and other proteins, extends across the cell between the centrioles as they move to opposite poles of the cell.
3. Metaphase:
The chromosomes line up neatly end-to-end along the centre (equator) of the cell.
The centrioles are now at opposite poles of the cell with the mitotic spindle fibres extending from them.
The mitotic spindle fibres attach to each of the sister chromatids.
4. Anaphase:
The sister chromatids are then pulled apart by the mitotic spindle which pulls one chromatid to one pole and the other chromatid to the opposite pole.
5. Telophase:
At each pole of the cell a full set of chromosomes gather together.
A membrane forms around each set of chromosomes to create two new nuclei.
The single cell then pinches in the middle to form two separate daughter cells each containing a full set of chromosomes within a nucleus. This process is known as cytokinesis.
2)Meosis
Meiosis is a process where a single cell divides twice to produce four cells containing half the original amount of genetic information. These cells are our sex cells – sperm in males, eggs in females.
During meiosis one cell? divides twice to form four daughter cells.
These four daughter cells only have half the number of chromosomes? of the parent cell – they are haploid.
Meiosis produces our sex cells or gametes? (eggs in females and sperm in males).
Meiosis can be divided into nine stages. These are divided between the first time the cell divides (meiosis I) and the second time it divides (meiosis II):
Meiosis I
1. Interphase:
The DNA in the cell is copied resulting in two identical full sets of chromosomes.
Outside of the nucleus? are two centrosomes, each containing a pair of centrioles, these structures are critical for the process of cell division?.
During interphase, microtubules extend from these centrosomes.
2. Prophase I:
The copied chromosomes condense into X-shaped structures that can be easily seen under a microscope.
Each chromosome is composed of two sister chromatids containing identical genetic information.
The chromosomes pair up so that both copies of chromosome 1 are together, both copies of chromosome 2 are together, and so on.
The pairs of chromosomes may then exchange bits of DNA in a process called recombination or crossing over.
At the end of Prophase I the membrane around the nucleus in the cell dissolves away, releasing the chromosomes.
The meiotic spindle, consisting of microtubules and other proteins, extends across the cell between the centrioles.
of the cell a full set of chromosomes gather together.
3. Metaphase I:
The chromosome pairs line up next to each other along the centre (equator) of the cell.
The centrioles are now at opposites poles of the cell with the meiotic spindles extending from them.
The meiotic spindle fibres attach to one chromosome of each pair.
4. Anaphase I:
The pair of chromosomes are then pulled apart by the meiotic spindle, which pulls one chromosome to one pole of the cell and the other chromosome to the opposite pole.
In meiosis I the sister chromatids stay together. This is different to what happens in mitosis and meiosis II.
5. Telophase I and cytokinesis:
The chromosomes complete their move to the opposite poles of the cell.
At each pole of the cell a full set of chromosomes gather together.
A membrane forms around each set of chromosomes to create two new nuclei.
The single cell then pinches in the middle to form two separate daughter cells each containing a full set of chromosomes within a nucleus. This process is known as cytokinesis.
Meiosis II
6. Prophase II:
In each of the two daughter cells the
7. Metaphase II:
8. Anaphase II:
..
9. Telophase II and cytokinesis:
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Answer:
Cell division is the process by which a parent cell divides into two or more daughter cells. Cell division usually occurs as part of a larger cell cycle. ... Meiosis results in four haploid daughter cells by undergoing one round of DNA replication followed by two divisions.
Two types are mitosis and meiosis
- There are two types of cell division: mitosis and meiosis. Most of the time when people refer to “cell division,” they mean mitosis, the process of making new body cells. Meiosis is the type of cell division that creates egg and sperm cells
Explanation:
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