Question

Study the diagram showing meiosis carefully and choose the correct options for A–E

(correct answer + 1, wrong answer - 0.25)

• A. A-Tetrad, B-Bivalent, C-Diplotene stage, D-Sister chromatids, E-Non-sister chromatids
• B. A- Bivalent, B- Tetrad, C-Diakinesis stage, D-Crossing over, E-Non-sister chromatids
• C. A- Bivalent, B- Tetrad, C- Pachytene stage, D- Non-sister chromatids, E- Sister chromatids
• D. A- Bivalent, B- Tetrad, C- Diplotene stage, D-Sister chromatids, E- Non-sister chromatids

Answer 1

The correct option is C A- Bivalent, B- Tetrad, C- Pachytene stage, D- Non-sister chromatids, E- Sister chromatids

(A) Tetrad: In pachytene stage, the chromatids of each synapsed chromosome slightly separate and become visible. The two visible chromatids of a chromosome are referred to as a dyad. A group of four homologous chromatids (two dyads) is called a tetrad.

(B) Bivalent: A pair of homologous chromosomes lying together is called a bivalent.

(C) Pachytene Stage: Tetrad formation is visible for the first time during pachytene stage where the paired homologous chromosomes become clearly visible.

(D) Non-sister Chromatids: The two chromatids of two homologous chromosomes (bivalent) are termed non-sister chromatids.

(E) Sister Chromatids: The two chromatids of the same chromosome are called sister chromatids.