Question

Match the stages of meiosis in column I to their characteristic features in column II and select the correct option:

Column I	Column II
A. Pachytene	(i) Synapsis
B. Anaphase I	(ii) Terminalisation of chiasmata
C. Diakinesis	(iii) Crossing­ over
D. Zygotene	(iv) Homologous chromosomes separate

• A. A-­(iii), B-­(iv), C-­(ii), D-­(i)
• B. A-­(i), B-­(iv), C­-(ii), D-­(iii)
• C. A-­(ii), B-­(iv), C-­(iii), D-­(i)
• D. A­-(iv), B-­(iii), C-­(ii), D-­(i)

Answer 1

The correct option is A A-­(iii), B-­(iv), C-­(ii), D-­(i)

Meiosis is a type of reductional division in which a parent cell divides to form into four daughter cells. Meiosis includes two sequential cycles of nuclear division and cell division called meiosis-I and meiosis-II.

Meiosis-I includes four phases - prophase-I, metaphase-I, anaphase-I and telophase-I.

Meiosis-II includes four phases - prophase-II , metaphase-II, anaphase-II and telophase-II.

Prophase-I is of long duration and is divided into five sub stages - leptotene, zygotene, pachytene, diplotene and diakinesis.

During zygotene, the pairing of homologous chromosomes occurs and this is called synapsis.

During pachytene, the non sister chromatids of homologous chromosomes exchange the genetic material and this leads to recombination of genetic material.

During diakinesis, the terminalisation of chiasmata occurs and this leads to separation of homologous chromosomes. Chiasmata are X shaped structures that indicate sites of crossing over.

During Anaphase-I, the homologous pair of chromosomes separate.