Describe meiosis 1 and meiosis 2?

Answer 1

Just before meiosis I there is Interphase I where there is DNA replication, organelle synthesis and an increase in energy stores. Then: Prophase I - Chromatin condenses into chromosomes and there is crossing over of non-sister chromatids, the nuclear membrane disappears, centrioles replicate and move to either pole of the cell. Metaphase I - the pairs of homologous chromosomes move to centre of cell - there is independent assortment. They are held in the centre of the cell by the spindle fibres which are made by the centrioles. Anaphase I - chromosomes are pulled to either pole as spindle fibres contract. The spindle fibres areattached to the centromeres of the chromosomes. Telophase I - the chromosomes reach either pole of the cell, and then there is cytokinesis and cell starts to divide. Prophase II - there is again the disappearance of the nuclear membrane and centrioles move to either pole. Metaphase II - the chromatids line up along equator of cell - again there is independent assortment Anaphase II - the chromatids are pulled to either pole as spindle fibres contract. Telophase II - the chromatids reach either pole, nuclear membrane reforms, and nucleolus reappears. Meiosis is completed! Those are all the stages of meiosis.

Answer 2

prophase I metaphase I anaphase I telophase I and cytokinesis prophase II metaphase II anaphase II telophase II and cytokinesis
There are 4 phases in meiosis phase 1. They are the prophase, the metaphase, the anaphase and the telophase.

Answer 3

"Meiosis is a special type of cell division. Unlike mitosis, the way normal body cells divide, meiosis results in cells that only have half the usual number of chromosomes, one from each pair."

Answer 4

Meiosis is the process of producing sperm and eggs(gametes). It is a reduction division, reducing the chromosome number to half the species chromosome number.

Meiotic division involves two steps.

1. The first meiotic division separates the homologous pairs or chromosomes and is therefore known as reduction division because it reduces the chromosome number to n. Just prior to this separation, the pairs of chromosome twist around each other, break, exchange segments, and rejoin. This is called crossing-over and results in genetic variations.

2. The second meiotic division separates the replicated chromosomes.

Results of meiotic Cell Division: as a result of the two divisions of meiosis, four cells are produced. Each new cells contains the monoploid number of chromosomes and is known as a gamete. The details or meiosis differ in males and females.

1. OOGENESIS: Meiosis in females occurs in the female gonad or ovary, and results in the female gamete called the ovum(egg). The ovum is larger than the sperm and contains stored nutrients in the form of yolk. Only one monoploid egg cell is formed from each primary sex cell than undergoes meiosis and maturation.

2. SPERMATOGENESIS: Meiosis in males occurs in the male gonads(testes), and produces male gametes called sperm, Each primary sex cell usually matures into four sperm cells. The sperm cells are very tiny compared to the egg and have a tail that they use to swim to the egg

Answer 5

Meiosis 1

Prophase consisting of Leptotene, Zygotene, Pachytene, Diplotene, Diakinesis

Metaphase 1

Anaphase 1

Telophase 1

Metaphase 2

Anaphase 2

telophase 2

Answer 6

what are the different phase of meiosis