Question

If the root of a diploid angiospermic plant has 42 chromosomes, find out the chromosome number in its synergid.

• A. 7
• B. 14
• C. 21
• D. 28

Answer 1

The correct option is C 21

Synergids are the two cells present in the egg apparatus, formed after megasporogenesis. It is a haploid cell as it is formed after meiosis and hence, has haploid number of chromosomes.

Root is the vegetative part of a plant. Since the plant is diploid, every cell of the root contains a diploid set of chromosomes. Given that the diploid number of chromosomes is 42, then the root will be having 42 chromosomes in their cells. (2n = 42)
Hence, the number of chromosomes in a haploid cell (synergid), n = 21.