Select the incorrect statement

Options

A. Zygote is thick walled diploid sexual spore
B. Flowers are bisexual in sweet potato
C. Ulothrix shows external fertilisation
D. The nucule in Chara has a cap of five coronary cells

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks us to identify the incorrect statement from a list of statements regarding reproduction in organisms.

2. **Analyzing the Statements**:
- **Statement 1**: "The zygote is a thick-walled diploid sexual spore."
- **Analysis**: This statement is incorrect. A zygote is formed by the fusion of male and female gametes, resulting in a diploid cell. It is not classified as a spore.

- **Statement 2**: "The flowers are bisexual in sweet potato."
- **Analysis**: This statement is correct. Sweet potato flowers contain both male (stamens) and female (carpels) reproductive organs.

- **Statement 3**: "Eulothrix shows external fertilization."
- **Analysis**: This statement is correct. Eulothrix, being a green filamentous algae, releases gametes into the external environment where fertilization occurs.

- **Statement 4**: "The nicule in Chara has a cap of 5 coronary cells."
- **Analysis**: This statement is correct. The female sex organ (nicule) in Chara does have a cap of five coronary cells.

3. **Conclusion**: The only incorrect statement is the first one, which mischaracterizes the zygote.

**Final Answer**: The incorrect statement is: "The zygote is a thick-walled diploid sexual spore."

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