Given below are the stages in the life cycle of pteridophytes. Arrange the following stages in the correct sequence.
A. Prothallus stage
B. Meiosis in spore mother cells
C. Fertilisation
D. Formation of archegonia and antheridia in gametophyte.
E. Transfer of antherozoids to the archegonia in presence of water.
Choose the correct answer from the options given below:

Question

Question

This question was previously asked in

NEET 2025 Official Paper (Held On: 04 May, 2025)

Answer 1

The correct answer is B, A, D, E, C

Concept:

Pteridophytes are a group of vascular plants that reproduce via spores and do not produce seeds or flowers. Their life cycle follows an alternation of generations, involving a diploid sporophytic generation and a haploid gametophytic generation.
The life cycle of pteridophytes includes several key stages: spore formation through meiosis, germination of spores into a gametophyte (prothallus), development of sex organs (archegonia and antheridia), fertilization, and the formation of a new sporophyte.

Explanation:

Step B: Meiosis in spore mother cells: The life cycle begins with meiosis in the spore mother cells of the sporophyte, resulting in the production of haploid spores. This marks the transition from the diploid sporophytic phase to the haploid gametophytic phase.
Step A: Prothallus stage: The haploid spores germinate to form a small, heart-shaped structure called the prothallus (gametophyte). This is the gametophytic stage in the life cycle.
Step D: Formation of archegonia and antheridia in gametophyte: The prothallus develops specialized structures—archegonia (female sex organs) and antheridia (male sex organs)—which produce eggs and antherozoids (male gametes), respectively.
Step E: Transfer of antherozoids to the archegonia in presence of water: Water plays a crucial role in the transfer of antherozoids to the archegonia, allowing fertilization to occur. This step requires a moist environment for the motile sperm to reach the egg.
Step C: Fertilization: Fertilization occurs within the archegonium, resulting in the formation of a diploid zygote. The zygote develops into a new sporophyte, completing the life cycle.