Question

Which one of the following is a correct statement?

• A. Pteridophytic gametophyte has a protonemal and a leafy stage
• B. In gymnosperms, the female gametophyte is free-living
• C. Antheridiophores and archegoniophores are present in pteridophytes
• D. Origin of seed habit can be traced to pteridophytes

Answer 1

The correct option is D Origin of seed habit can be traced to pteridophytes

The gametophytic stage of Pteridophytes is called prothallus, which is a free-living, very small, green, thalloid structure. The protonemal and leafy stages are characteristics of the gametophytes of mosses.

In gymnosperms, the gametophyte, either male or female, is completely dependent on the sporophyte and cannot exist by itself.

Antheridiophores and archegoniophores are stalk-like structures seen in liverworts (e.g. Marchantia) upon which the antheridia and archegonia are borne. They are not present in pteridophytes.

In heterosporous pteridophytes, the female gametophyte remains on the parent sporophyte for variable periods. The development of the zygote into the young embryo takes place within the female gametophyte. This event is a precursor to the seed habit and hence the origin of the seed habit is said to be in pteridophytes. Hence Option D is the correct statement.