Concept explainers
During meiosis I
- Homologous chromosomes synapse.
- Crossing over between homologous chromosomes occurs.
- the chromosomal number is reduced by half.
- the haploid cells are produced.
- All of these are correct.
Introduction:
The process of DNA replication is the process by which the genetic material of the organism copies itself to be distributed among the daughter cells during cell division. The DNA replication takes place before the cell division and prepares the cell for mitosis and meiosis. This process is followed by transcription and translation.
Answer to Problem 1RAC
The correct answer is option (e) all of these are correct.
Explanation of Solution
Explanation/justification for the correct answer:
Option (e) all of these are correct. The meiosis or the reductional division reduces the chromosome number in the two haploid cells by half and consists of crossing over at the synapse. So, the correct answer is option (e).
Explanation for incorrect answer:
Option (a) homologous chromosomes synapse. The meiotic division allows the recombination to occur between the homologous chromosomes at the synapse and allows the exchange of the genetic material, but that is not the only characteristic of meiosis. So, this is an incorrect option.
Option (b) crossing over between homologous chromosomes occurs. During meiosis, the crossing over takes place between the homologous chromosomes that allow the two chromosomes to exchange the genetic material, but that is not the only characteristic of meiosis. So, this is an incorrect answer.
Option (c) the chromosome number is reduced by half. The chromosome number is reduced to half from diploid cell to haploid gametes that give rise to diploid zygote, but that is not the only characteristic of meiosis. So, this is an incorrect answer.
Option (d) two haploid cells are produced. The diploid cell results in the production of two cells that are haploid in nature as the chromosome number is reduced to half during the meiotic divisions, but that is not the only characteristic of meiosis. So, this is an incorrect answer.
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