Q24. Label the elements of the fern life cycle diagram: sporangium, meiosis, spore, gametophyte, antheridium, archegonium, sperm, egg, fertilization, and zygote.

Background

Topic: Alternation of Generations in Seedless Vascular Plants (Ferns)

This question tests your understanding of the fern life cycle, which features alternation of generations. You need to identify key stages and structures involved in reproduction, including both haploid and diploid phases.

Key Terms and Concepts:

• Sporangium: Structure where spores are produced by meiosis.

• Meiosis: Cell division that reduces chromosome number, producing haploid spores.

• Spore: Haploid cell that grows into the gametophyte.

• Gametophyte: Haploid generation that produces gametes.

• Antheridium: Male gametophyte organ producing sperm.

• Archegonium: Female gametophyte organ producing eggs.

• Fertilization: Fusion of sperm and egg to form a zygote.

• Zygote: Diploid cell formed after fertilization, grows into the sporophyte.

Step-by-Step Guidance

1. Start by identifying the two main generations in the diagram: the sporophyte (fern plant) and the gametophyte (small, heart-shaped structure).

2. Locate the sporangium on the sporophyte. This is where meiosis occurs, producing haploid spores.

3. Follow the arrows from the sporangium to the spores. These spores are released and germinate to form the gametophyte.

4. On the gametophyte, identify the antheridium (male) and archegonium (female) structures. These produce sperm and eggs, respectively.

5. Trace the path of sperm from the antheridium to the egg in the archegonium, leading to fertilization and formation of the zygote.

6. After fertilization, the zygote develops into a new sporophyte, completing the cycle.

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