Question

Diakinesis can be observed best in
A. Onion root tip
B. Leaf of Dichanthium
C. Rat tail
D. Flower bud

Answer 1

Hint: Diakinesis is a phase of Meiosis. Meiosis is the reductional division in which four cells are formed from one cell and the chromosome number of each cell is halved of the original. Moreover, the meiosis was first observed by Moore and Farmer. Meiosis occurs in only the reproductive parts of the organisms.

Complete step-by-step answer:
The prophase I of meiosis is divided into five phases. These five phases, in the order of their occurrence, are Leptotene, Zygotene, Pachytene, Diplotene, and Diakinesis. The Diakinesis is the last phase of Prophase I of meiosis.
During diakinesis, the nuclear membrane and the nucleolus gradually disappear. Before this, in the previous four phases, the nuclear membrane and nucleolus remain absolutely intact. The chromosomal condensation continues here. Moreover, the centriole pairs move towards the opposite poles. The formation of the astral rays begins.
The flower bud is the reproductive part of the plant. These cells divide with the help of the meiotic division. This is because the cells of the reproductive parts of the plant divide with the help of meiosis but the vegetative parts of the plant do not divide with the help of meiotic divisions.
Thus, based on the above information we can conclude that the diakinesis can be observed best in the flower bud.

Hence, the correct answer is an option (D).

Note : Meiosis is divided into four main phases just like mitosis. These four phases are the prophase, metaphase, anaphase, telophase. However, in meiosis two divisions occur due to which each phase has two occurrences that are named as I and II respectively.