Question

If a diploid cell contains six chromosome, how many possible random arrangement of homologous could occur during metaphase-1

Answer 1

The question is finding the possibilities of arranging the number of chromosomes on the metaphase plate during Metaphase 1. Hence it is a meiotic division.

During meiotic division, pairing of the homologous pair of chromosomes will take place. The synaptonemal complex will arise in between the two homologous pairs during the Zygotene stage. Hence the tetrad or bivalent will be formed.

Now the arrangement of tetrad is random. Each divalent chromosomes will have two possible arrangement.

Hence,

6 chromosomes = 3 bivalents.

Each bivalent has 2 possible arrangement.

Therefore, the possible arrangement of the chromosomes will be 2*2*2 = 8.

Hence there are 8 possible random ways the bivalents can arrange themselves on the metaphase plate.

Answer 2

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