Comparing mitosis and meiosis Transitional Reasoning Download PDF

Questions

1. 1.

   A cytogeneticist analyzes dividing cell samples from a diploid mammal with $2n = 16$. Sample P displays homologous chromosome pairing into tetrads and reciprocal genetic exchange prior to chromosome segregation, yielding daughter cells that each contain 8 replicated chromosomes. In contrast, Sample Q displays individual chromosomes aligning independently along the equatorial plane before sister chromatids separate, yielding daughter nuclei with 16 chromosomes each. Based on these observations, which statement correctly compares the division mechanisms occurring in Sample P and Sample Q?

   • A) Sample P undergoes meiosis, producing genetically diverse haploid daughter nuclei, whereas Sample Q undergoes mitosis to generate genetically identical diploid nuclei.
   • B) Sample P undergoes mitosis, which introduces genetic variation via homologous recombination, whereas Sample Q undergoes meiosis II directly without an intervening S phase.
   • C) Sample P halves chromosome number by separating sister chromatids in its first division, whereas Sample Q duplicates its homologous pairs without cytokinesis.
   • D) Both samples undergo different stages of mitosis, with Sample P representing an atypical somatic polyploidization and Sample Q representing standard diploid karyokinesis.