Question

Life cycle of gymnosperm is
A. Haplontic
B. Haplodiplontic
C. Diplontic
D. Diplohaplontic

Answer 1

Hint: Gymnosperms are the smallest group of plants. They contain all the terrestrial plants only. The word gymnosperm is made up of two words, gymnos meaning naked, and sperma meaning seeds. These plants, therefore, have naked seeds.

Complete answer:
Gymnosperms are mostly shrubs and trees. The formation of seeds first occurred in the gymnosperms. Due to this reason, they are known as the spermatophytes or the seed-bearing plants. These plants have clearly differentiable roots, stems, and leaves. There is no formation of fruits in these plants. this is because ovules are present but ovaries are absent. Due to this reason, they are known as naked seed plants. These plants are very localized and they are getting extinct rapidly because their seeds are naked. As they have no fruits for the dispersion of the seeds and for protecting them from harsh environmental conditions, therefore, it is causing their rapid extinction.
The main body of gymnosperms is sporophytic and diploid. However, their gametes are haploid. Due to this reason, they have a diplontic life cycle. This is because most parts of their life cycle are diploid. Only the female gametophyte and the pollen grains are haploid.
Thus, based on the above information we can conclude that the life cycle of gymnosperms is Diplontic.
Hence, the correct answer is option (C).

Note: A diplontic life cycle is the one that has haploid gametes and their main bodies are sporophytic. Apart from gymnosperms, angiosperms also have a diplontic life cycle. Fucus which is a type of brown algae of Phaeophyceae also has a diplontic life cycle.