Question

Which of the following is not the product of fertilization
(a) Zygote in algae
(b) Seeds of cycas
(c) Fruit of mango
(d) Endosperm of cotton

Answer 1

Hint: Organisms or species that show the haplontic life cycle and haplodiplontic life cycle in which zygote is formed without fusion of cells or nuclear material.

Complete step by step answer:
Reproduction in algae occurs by three methods namely sexual reproduction, asexual reproduction, and vegetative propagation. Organisms like Chlamydomonas exhibit a haplontic life cycle where mitosis occurs only in a haploid cell resulting in the formation of single haploid organisms. In members of algae, the new progeny is produced without fusion of cells or nuclear materials so the zygote formed will not be the product of fertilization.

Additional information:
- Asexual reproduction in algae occurs via fragmentation and spores and sexual reproduction occur via the fusion of gametes.
- Algae exhibit both haplontic and haplo-diplontic types of the life cycle. The majority of algae shows haplo-diplontic life cycle’
- In the haplo-diplontic life cycle mitosis occurs in both haploid cells and diploid cells
- Algae which exhibits this type of life cycle shows a phenomenon called ‘alternation of generations’
- In general, seed are the products of fertilization but in some species of the family Asteraceae and grasses seed is developed without fertilization, called apomixis
- After fertilization ovary is developed into fruit but in some plants like bananas, grapes fruits are produced without fertilization, such types of fruits are called parthenocarpic fruits and the process is called parthenocarpy.
- In some plants like mango and citrus seeds contain more than one ovary, it is called polyembryony.
So, the correct answer is ‘zygote in algae’.

Note:
- Seeds are absent in parthenocarpic fruits.
- If the hybrid seeds are made into apomicts there will be no segregation of characters and can be used repeatedly