Question

Refer to the given flow chart regarding different groups of Kingdom Plantae. Which of the following is true regarding P, Q, R, S, and T?

(a)Examples of ‘P’ include Riccia, Marchantia, Sphagnum, etc
(b)Members of group ‘R’ can be both homosporous as well as heterosporous.
(c)Group ‘Q’ includes seedless vascular plants having a sporophytic plant body.
(d)Group ‘s” is more ancient than group ‘T’ and formed dominant vegetation on Earth some 200 million years back in the Mesozoic era.

Answer 1

Hint: Kingdom Plantae is mainly divided into two groups based on the non- flowering plants known as Cryptogamia and flowering plants known as Phanerogamia.

Complete answer:
In algae the sex organs are non- jacket a unicellular thus ‘P’ refers to Algae. Unlike algae, Bryophyta has a flask-shaped structure with a swollen base known as venter surrounded to one-celled thick sterile jacket layer and upper elongated neck, but have a dominant gametophyte phase where the adult sporophyte is dependent for nutrition due to early development of embryo sporophyte is nurtured by the gametophyte. Thus, ‘R’ refers to bryophytes. In gymnosperms the endosperm is formed during the germination of the megaspore in the ovule and becomes prothallus or gametophyte consists of a haploid set of chromosomes thus, ‘T’ is a gymnosperm. Whereas in angiosperm the endosperm is triploid because of double fertilization results in the formation of diploid zygote and triploid endosperm thus, ‘S’ refers to angiosperm.

Additional Information: -Under Cryptogamia is further divided into – Thallophyta, Bryophyta, and Pteridophyta.
-Under Phanerogamic is further divided into – Gymnosperms and Angiosperms.
So, the correct answer is ‘Group ‘Q’ includes seedless vascular plants having a sporophytic plant body’.

Note: -Cryptogams are a type of plant which reproduces by spores without flowers or seeds. Cryptogame means ‘hidden’ where the plant shows hidden reproduction where no seed is produced thus, refers to non- seed-bearing plants.
- Condition, where the fertilization takes before the fusion of gametes, is termed as pre- fertilization.