Question

Which of the following statements about meiosis in sexually reproducing plants is INCORRECT?

• A. The end products of meiosis II are haploid gametes.
• B. The four products of meiosis are genetically different.
• C. Meiotic recombination takes place in both males and females.
• D. In most flowering plants, only one of the four products of meiosis survives in females.

Hint:

Always pay attention to the organism group mentioned in the question.
Plants undergo sporic meiosis (forming spores), whereas animals undergo gametic meiosis (forming gametes).
Keeping this distinction in mind prevents easy mistakes.

Answer 1

The Correct Option is A

Step 1: Understanding the Question:
The question asks us to identify the incorrect statement regarding meiosis in sexually reproducing plants.

Step 2: Key Formula or Approach:
Let's review the fundamental differences between plant and animal life cycles:
1. In animals, meiosis directly produces haploid gametes (sperm and egg), a process known as gametic meiosis.
2. In plants, meiosis is sporic. It occurs in sporophytes to produce haploid spores (microspores and megaspores). These spores undergo mitosis to form multicellular gametophytes (pollen grain and embryo sac) which then produce gametes.

Step 3: Detailed Explanation:
Let us evaluate each of the given statements:
- Statement (A): "The end products of meiosis II are haploid gametes."
- In plants, the direct products of meiosis II are haploid spores (sporic meiosis), not gametes.
- For example, microsporogenesis produces four microspores, which develop into pollen grains (male gametophyte) that subsequently produce male gametes via mitosis.
- Thus, this statement is biologically incorrect for plants.
- Statement (B): "The four products of meiosis are genetically different."
- This is correct. Crossing over (recombination) during Prophase I and independent assortment of chromosomes during Metaphase I ensure genetic diversity.
- Statement (C): "Meiotic recombination takes place in both males and females."
- This is correct. Recombination occurs in both microsporogenesis (male) and megasporogenesis (female) to generate genetic diversity.
- Statement (D): "In most flowering plants, only one of the four products of meiosis survives in females."
- This is correct. During megasporogenesis, a single megaspore mother cell undergoes meiosis to produce a linear tetrad of four haploid megaspores.
- In the vast majority of angiosperms (monosporic development), three of these megaspores degenerate, and only one survives to develop into the functional embryo sac.

Step 4: Final Answer:
Since statement (A) is incorrect, it is the correct choice.