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Question: In gymnosperms, A. Male and female gametophytes are independent of sporophyte. B. Male and femal...

In gymnosperms,
A. Male and female gametophytes are independent of sporophyte.
B. Male and female gametophytes are dependent on sporophyte
C. Ovary represents megasporangium
D. Embryo sac represents female gametophyte

Explanation

Solution

Gymnosperms are plants with naked seeds, the gametophytes have only one pair of chromosomes which is highly reduced and dependent and they are the initial generation in the alternation of generation.

Complete answer:
Gymnosperms are plants without flowers and the seeds in these plants are not enclosed within an ovary.
-Plants undergo alternation of generation. The first is a haploid generation and the other one is a diploid generation. The diploid generation is called sporophyte and the haploid generation is known as a gametophyte. A diploid has pairs of chromosomes whereas a haploid has only one set of chromosomes.
-From the diagram below, we get an idea of how alternation of generation in plants takes place.

-In option A, it is mentioned that male and female gametophytes are independent of the sporophyte. This is true. The male gametophytes are produced within microsporophylls and are haploid in nature. The female gametophytes are produced by the meiotic division of megaspore mother cells. Four megaspores are formed out of which the only one becomes the female gametophyte. Therefore, all of them are haploid.
-In option B, it is mentioned that male and female gametophytes are dependent on sporophyte. We can say this is false because both of them are independent of sporophytes.
-In option C, it is mentioned that the ovary represents megasporangium. This is incorrect because an ovule is equivalent to megasporangium. The ovary or the female organ of the part contains ovules, which form seeds.
-In option D, it is mentioned that the embryo sac represents female gametophyte. This is correct but only for angiosperms.
Hence option A is correct.

Note: Unlike gametophytes, sporophytes depend on gametophytes for nutrition. The cells of sporophyte divide by the process of meiosis to produce spores, which then undergo double fertilization. The male spores travel through wind, water, or animals to the female organ to mate.