Question

The image below shows two germinated seeds X and Y which belong to the same species. Seed X is produced by apomixis whereas seed Y is a product of sexual reproduction.

1. Write the number of embryo(s), embryo sac(s) and ovules in the ovary of seed X.
2. How multiples embryos are formed in citrus fruits?
3. What advantage will plants developed from seed Y have over seed X?

Answer 1

1. Seed X- 3 embryos; 1embryo sac; 1ovule;
2. The nucellar cells grow mitotically and develop into embryos by asexual reproduction.
3. The plants growing from seed X will have to share the resources/endosperm so there is a possibility of some plant being undernourished/; only one plant in seed Y will use the entire endosperm for its growth or as the plants of seed X are clones they will not show variation and may succumb to environmental stress;/ plants from seed Y will have genetic variation and so can show greater adaptability.