Question

Arrange the following division in the correct sequence of the progressive evolution in their haploid phase (Gametophyte)
I. Thallophyta
II. Bryophyta
III. Pteridophyta
IV. Spermatophyte
A. IV, III, I, II
B. IV, III, II, I
C. IV, II, III, I
D. II, I, III, IV

Answer 1

Hint: Organic evolution involves the formation of newer or more complex types of organisms from the pre-existing simpler organisms through modifications. It is of various types like progressive, retrogressive, divergent, convergent, microevolution and macroevolution,

Complete answer: Progressive evolution is the formation of more complex, elaborate and specialized structures from the single structure.
Thallophyta- It includes the most primitive plants. The plant body is either unicellular or multicellular thallus. Algae, fungi, bacteria and lichens are the four groups of thallophyta.
There is regular alternation of haploid gametophyte and diploid sporophytic generations in the life cycle of the alga.
Bryophyta- They are found in moist, shady and cold places and constitute liverworts and mosses. Gametophytic and sporophytic are the two phases of the life cycle of bryophytes. The gametophytic phase is haploid, long-lived, dominant, and green and independent while the diploid sporophyte depends upon the gametophyte and is short lived.
Pteridophyta- These are vascular cryptogams and their plant body is differentiated into roots, stems and leaves. They can be either heterosporous or homosporous and the spores are produced inside the sporangia on leaves. The main independent plant body here is sporophyte. Prothallus which is the haploid gametophyte is formed from the spore germination.
Spermatophytes include gymnosperms and angiosperms that are seed producing plants. These plants are mainly sporophytic and they produce gametes at the time of sexual reproduction.
So, the correct answer is “Option A”.

Note:
-All the stages through which an organism passes from the zygote of one generation to the zygote of the next generation constitute its life cycle.
-Alteration of spore producing diploid sporophyte with the haploid gametophyte is called alternation of generations and it occurs in most of the plants.