Question

Arrange the given stages of Megasporogenesis in chronological order.
(A) Megaspore tetrad
(B) Megaspore dyad
(C) Megaspore mother cell
(D) Female gametophyte
Choose the correct answer from the options given below:

• A. (D), (A), (B), (C)
• B. (A), (D), (C), (B)
• C. (B), (A), (D), (C)
• D. (C), (B), (A), (D)

Answer 1

The Correct Option is D

To understand the stages of megasporogenesis and arrange them chronologically, we need to grasp what each stage represents in the process of forming a female gametophyte from a megaspore mother cell. Here's the process: 

1. Megaspore Mother Cell (C): This is the initial stage where a diploid cell, the megaspore mother cell, is ready to undergo meiosis.
2. Megaspore Dyad (B): After the first meiotic division, the megaspore mother cell divides into two haploid cells called the megaspore dyad.
3. Megaspore Tetrad (A): Following the second meiotic division, each cell of the dyad splits again to form four haploid cells, known as the megaspore tetrad.
4. Female Gametophyte (D): Typically, one of these haploid cells develops further into the female gametophyte, while the rest often degenerate. This gametophyte will give rise to the egg cell.

Accordingly, the correct chronological order of these stages is: (C), (B), (A), (D).

Answer 2

The process of megasporogenesis involves the development of the female gametophyte from a megaspore mother cell through a series of stages. Here's the correct order:

(C) Megaspore mother cell: This is the diploid cell that undergoes meiosis to form haploid megaspores.

(B) Megaspore dyad: After meiosis, the megaspore mother cell divides into two haploid cells (dyad), though in most plants, only one of the cells will continue to develop.

(A) Megaspore tetrad: Following the second meiotic division, the dyad divides further into four megaspores, forming a tetrad. However, in most plants, only one of the four megaspores will survive and become functional.

(D) Female gametophyte: The surviving megaspore undergoes mitotic divisions to form the female gametophyte (or embryo sac), which is the structure that produces the egg cell.

Thus, the correct chronological order is: (C), (B), (A), (D).

Correct Answer: (4) (C), (B), (A), (D).