Question

which letter in figure 19.7 identifies a primary spermatocyte?
options: b, a, d, c

Explanation:

To identify the primary spermatocyte, we recall the stages of spermatogenesis. Primary spermatocytes are in the first meiotic division, with duplicated chromosomes (tetrads or synapsed homologs). Looking at the figure:

• A: Likely a spermatogonium (diploid, undivided chromosomes).
• B: Shows chromosomes in synapsis (tetrads), characteristic of primary spermatocytes (undergoing meiosis I).
• C: Likely secondary spermatocytes (haploid, post - meiosis I).
• D: Sperm cells (mature, haploid, flagellated).

So, B corresponds to the primary spermatocyte.

Answer:

B