Question

Give an example of plants with

a. Haplontic life cycle

b. Diplontic life cycle

c. Haplo-diplontic life cycle

Answer 1

a. Haplontic life cycle:

● The dominant phase in their life cycle is haploid.

● The main vegetative plant body is haploid. It produces male and female gametes.

● Zygote (formed after fusion of the male and female gamete) are the only diploid stage. Subsequent meiosis gives rise to haploid spores.

● These haploid spores then form haploid plants.

● Algae/ thallophytes usually exhibit a haplontic life cycle.

Example: Chlamydomonas

Final answer:

Chlamydomonas

b. Diplontic life cycle:

● The dominant phase in their life cycle is diploid.

● The main vegetative plant body is diploid.

● Gametes produced after meiosis are haploid and fuse to form diploid zygotes.

● Gymnosperms and angiosperms usually exhibit a diplontic life cycle.

Example: Cycas

Final answer:

Cycas​

c.​​​​​​ Haplo-diplontic life cycle:

● The gametophytic plant body is haploid which produces haploid gametes. These gametes fuse to produce diploid zygotes.

● It germinates to produce a diploid sporophytic plant body which produces haploid spores. The spores germinate to produce haploid gametophytic plant bodies.

● These two phases of gametophytes and sporophytes alternate with each other in the life cycle of the plant.

Example: Funaria

Final answer:

Funaria