Question

The dominant photosynthetic phase in the life cycle of pteriodophyta is equivalent to the

• A. Gametophytic phase of gymnosperm
• B. Sporophytic phase of bryophyte
• C. Gametophytic phase of pteridophytes
• D. Gametophytic phase of bryophyte

Answer 1

The correct option is D Gametophytic phase of bryophyte

Pteridophytes and Bryophytes show an intermediate life cycle, known as haplodiplontic life cycle, these phases are multicellular. However, the dominant phase differs. In bryophytes, the dominant phase is the gametophyte and in pteridophytes, it is the sporophyte.

In pteridophytes, the zygote or fertilized egg experiences mitotic division forming the different segments such as roots, stem, sporophyte and later on spores, which are again formed via meiosis and dispersed and hence the cycle goes on. Thus, the dominant phase is sporophyte.

While in bryophytes, the mature gametophyte produces both male and female gametes, which join to form a diploid zygote. The zygote develops into the diploid sporophyte, which extends from the gametophyte and produces haploid spores through meiosis. Once the spores germinate, they produce new gametophyte plants and the cycle continues.

Thus, the dominant photosynthetic phase(sporophyte)in the life-cycle of pteridophytes is equivalent to the dominant gametophytic phase of bryophytes.

Hence, option A is correct.