Q36. What phase of meiosis is seen in the figure to the right?

Background

Topic: Meiosis Phases

This question tests your understanding of the stages of meiosis, specifically how chromosomes behave and move during each phase. Recognizing the arrangement and movement of chromosomes is key to identifying the correct phase.

Key Terms:

• Metaphase: Chromosomes align at the cell's equator.

• Anaphase: Chromosomes (or chromatids) are pulled apart toward opposite poles.

• Meiosis I vs. Meiosis II: Meiosis I separates homologous chromosomes; Meiosis II separates sister chromatids.

Step-by-Step Guidance

1. Observe the image: Chromosomes are being pulled toward opposite poles of the cell.

2. Recall that in meiosis, this movement occurs during anaphase. In anaphase I, homologous chromosomes separate; in anaphase II, sister chromatids separate.

3. Examine the chromosome structure: Are the chromosomes single or double (X-shaped)? This helps distinguish between anaphase I and II.

4. Consider the context: If the chromosomes are X-shaped and being pulled apart, it suggests separation of sister chromatids, characteristic of anaphase II.

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Q48. Fill in the model below showing what the cell would look like throughout meiosis. Make sure that you accurately represent whether chromosomes are unreplicated or replicated, cell ploidy level.

Background

Topic: Chromosome Behavior in Meiosis

This question tests your understanding of chromosome number, replication status, and ploidy (haploid/diploid) at different stages of meiosis. You need to track how chromosomes change from the starting cell, through meiosis I, to meiosis II.

Key Terms:

• Replicated Chromosome: Two sister chromatids joined at the centromere (X-shaped).

• Unreplicated Chromosome: Single chromatid (I-shaped).

• Diploid (2n): Two sets of chromosomes.

• Haploid (n): One set of chromosomes.

Step-by-Step Guidance

1. Starting cell: Count the number of chromosomes (each X-shaped structure is a replicated chromosome). Determine if the cell is diploid or haploid based on chromosome pairs.

2. End of Meiosis I: Homologous chromosomes separate, resulting in two cells. Each cell has half the original chromosome number, but chromosomes are still replicated.

3. End of Meiosis II: Sister chromatids separate, resulting in four cells. Chromosomes are now unreplicated, and each cell is haploid.

4. For each stage, record: number of chromosomes, whether chromosomes are replicated or unreplicated, and ploidy level.

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