I am little confused about the ploidy of cell when it undergo meiosis 1.can anybody tell the ploidy of two daughter cells after completion of meiosis 1?

Question

Answer

Meiosis 1

Mitotic cell division is equational in nature while meiosis is a reduction division. The salient features of meiotic division that make it different from

mitosis

are as follows:-

It occurs in two stages of the nuclear and cellular division as Meiosis I and Meiosis II. DNA replication occurs, however, only once.
It involves the pairing of homologous chromosomes and recombination between them.
Four haploid daughter cells are produced at the end, unlike two diploid daughter cells in mitosis.

Meiosis 1 separates the pair of homologous chromosomes and reduces the diploid cell to haploid. It is divided into several stages that include, prophase, metaphase, anaphase and telophase.

Meiosis 1 Stages

The different stages of meiosis 1 can be explained by the following phases :

Prophase 1
Metaphase 1
Anaphase 1
Telophase

Phases of Meiosis 1

Meiosis 1 Prophase 1

Prophase I is longer than the mitotic prophase and is further subdivided into 5 substages,
- leptotene
- zygotene
- pachytene
- diplotene
- diakinesis
The chromosomes begin to condense and attain a compact structure during leptotene.
In zygotene, the pairing of homologous chromosomes starts a process known as chromosomal synapsis, accompanied by the formation of a complex structure called synaptonemal complex. A pair of synapsed homologous chromosome forms a complex known as bivalent or tetrad.
At pachytene stage, crossing over of non-sister chromatids of homologous chromosomes occurs at the recombination nodules. The chromosomes remain linked at the sites of crossing over.
Diplotene marks the dissolution of the synaptonemal complex and separation of the homologous chromosomes of the bivalents except at the sites of cross-over. The X-shaped structures formed during separation are known as chiasmata.
Diakinesis is marked by the termination of chiasmata and assembly of the meiotic spindle to separate the homologous chromosomes. The nucleolus disappears and the nuclear envelope breaks down.
Meiosis 1 Metaphase 1
The bivalents align at the equatorial plate and microtubules from the opposite poles attach to the pairs of homologous chromosomes.
Meiosis 1 Anaphase 1
The two chromosomes of each bivalent separate and move to the opposite ends of the cells. The sister chromatids are attached to each other.
Meiosis 1 Telophase 1
The
nuclear membrane
reappears and is followed by cytokinesis. This gives rise to a dyad of cells
Stages of Meiosis II
The four stages of meiosis II are as follows:-
- Prophase II – It immediately sets off after the cytokinesis when the daughter cells are formed. The chromosomes begin to condense accompanied by the dissolution of the nuclear membrane and the disappearance of the
  Golgi apparatus
  and ER complex.
- Metaphase II – The chromosomes are connected to the centriole poles at the kinetochores of sister chromatids through the microtubules. They also get aligned at the equator to form the metaphase plate.
- Anaphase II – In this phase of meiosis II, there is a simultaneous splitting of the centromere of each chromosome and the sister chromatids are pulled away towards the opposite poles. As the chromatids move towards the poles, the kinetochore is at the leading edge with the chromosomal arms trailing.
- Telophase II – The chromosomes dissolve again into an undifferentiated lump and a nuclear envelope develops around it. Followed by cytokinesis, telophase II marks the end of meiosis. Four haploid daughter cells are formed as a result.

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