Q1 Value based question:
In biology practical the teacher asked students to identify the stage of cells division in a slide focused undue microscope some said it is metaphase of mitosis and some said it is metaphase I of meiosis finally teacher told it is metaphase I of meiosis
a) On what basis the tea
cher confirmed that it is Metaphase I of meiosis
b) Enlist the difference between Metaphase II of meiosis
c) What is the significance of meiosis?

Dear student,
Please find below the solution to the asked query

(a) Teacher may have confirmed that it is Metaphase I of meiosis on the basis of presence of bivalent chromosomes with four chromatids in each on the equatorial plate. Also, here the arms of paired chromosomes lie on equatorial plate of spindle while as the centromeres are directed towards poles.

(b) 
Metaphase 1 of meiosis Metaphase 2 of meiosis
The bivalents (tetrads formed by pairing of synapsed chromosomes), are arranged at the equator in two parallel metaphase plates. The chromosomes become arranged at the equator of the spindle forming a single metaphase plate.
The arms of the chromosomes are at the right angles to the spindle fibres. The arms of chromosomes are not at right angles to the spindle fibres.

(c) 
1. It ensures the maintenance of a constant chromosome number, characteristic of a particular species, generation after generation.
2. The crossing over during meiosis results in the variation of genetic characters in offspring which serves as the raw material for evolution.

Hope this information will clear your doubts about the meiosis.
If you have any more doubts just ask here on the forum and our experts will try to help you out as soon as possible.
Regards  

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