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 between the gametophyte and sporophyte stages. You need to identify key structures and processes involved in reproduction and development.

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 a gametophyte.

• Gametophyte: Haploid stage that produces gametes (sperm and egg).

• Antheridium: Male gametophyte organ that produces sperm.

• Archegonium: Female gametophyte organ that produces eggs.

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

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

Step-by-Step Guidance

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

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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