Nucellus -2n
antipodal cells -n
egg nucleus -n
secondary nucleus can be n and 3n
MMC-2n


so egg and antipodal cells

In plants, the haploid number of chromosomes refers to the number of chromosomes present in the gametes or reproductive cells. These gametes are involved in sexual reproduction and combine to form a diploid zygote.

The correct answer to the given question is option C, which states that the haploid number of chromosomes is found in the egg and antipodal cells. Let's understand why this is the correct answer.


- The egg cells, also known as the female gametes, are produced in the ovules of the flower's pistil.
- The egg cells are haploid, meaning they contain half the number of chromosomes as compared to the other cells in the plant.
- The haploid number of chromosomes in egg cells is essential for sexual reproduction, as it allows for the fusion of gametes with the male gametes (pollen) during fertilization.


- Antipodal cells are one of the three types of cells found in the mature embryo sac or female gametophyte of flowering plants.
- They are located at the opposite end of the embryo sac from the egg cell.
- Antipodal cells are also haploid, containing the same number of chromosomes as the egg cells.
- The function of antipodal cells is not well understood, but they are believed to play a role in supporting the development of the embryo sac.



Let's analyze the other options to understand why they are not the correct answer:

a) Nucellus and antipodal cells:
- The nucellus is a part of the ovule and contains the megaspore mother cell, which undergoes meiosis to produce haploid megaspores.
- The antipodal cells are also present in the mature embryo sac, as explained earlier.
- Both the nucellus and antipodal cells are haploid, but the question asks for a pair of plant structures, and these two are not directly related.

b) Egg nucleus and secondary nucleus:
- The egg nucleus is the haploid nucleus present in the egg cell.
- The secondary nucleus, also known as the central cell, is involved in double fertilization in flowering plants and is typically diploid.
- Therefore, this pair does not fulfill the requirement of having a haploid number of chromosomes in both structures.

d) Megaspore mother cell and antipodal cell:
- The megaspore mother cell is a diploid cell located within the nucellus of the ovule.
- It undergoes meiosis to produce haploid megaspores, one of which develops into the embryo sac containing the antipodal cells.
- While the antipodal cells are haploid, the megaspore mother cell is diploid, so this pair does not have a haploid number of chromosomes in both structures.

Therefore, option C, which states that the egg and antipodal cells have a haploid number of chromosomes, is the correct answer.