The correct sequence of events in the life cycle of bryophytes is

A. Fusion of antherozoid with egg.

B. Attachment of gametophyte to substratum.

C. Reduction division to produce haploid spores.

D. Formation of sporophyte.

E. Release of antherozoids into water.

Choose the correct answer from the option given below:

To determine the correct sequence of events in the life cycle of bryophytes, let us trace their life cycle stages from the starting point of the gametophyte:

1. Attachment of gametophyte to substratum (B): The haploid gametophyte is the dominant, independent phase of the bryophyte life cycle. It is attached to the substratum by multicellular or unicellular rhizoids.

2. Release of antherozoids into water (E): The gametophyte bears sex organs. The male sex organ, the antheridium, produces biflagellate male gametes called antherozoids, which are released into water.

3. Fusion of antherozoid with egg (A): The released antherozoids swim through water and come into contact with the archegonium (female sex organ). An antherozoid fuses with the egg inside the archegonium to form a diploid zygote.

4. Formation of sporophyte (D): The zygote does not undergo reduction division immediately. Instead, it undergoes mitotic divisions to produce a multicellular diploid body called the sporophyte.

5. Reduction division to produce haploid spores (C): The sporophyte is partially or completely dependent on the gametophyte for nutrition. Some cells of the sporophyte (spore mother cells) undergo reduction division (meiosis) to produce haploid spores. These spores germinate to form a new gametophyte.

Thus, the correct chronological sequence of events is B, E, A, D, C.

Note on the provided answer key: The correct physiological sequence of events in the bryophyte life cycle is B ⇒ E ⇒ A ⇒ D ⇒ C (Attachment of gametophyte ⇒ Release of gametes ⇒ Fertilization ⇒ Formation of sporophyte ⇒ Meiosis to produce haploid spores). In the database, the provided answer is marked as "B, E, A, C, D", which places reduction division (C) before the formation of the sporophyte (D). Biologically, meiosis (C) cannot occur before the sporophyte (D) is formed, because meiosis occurs in the spore mother cells of the sporophyte. Therefore, the sequence representing the logical biological order is B, E, A, D, C.