Which of the following is an incorrect statement ?

Options

A. Brown algae has chlorophyll a and c, and fucoxanthin
B. Archegonia are found in Bryophyta , pteridophyta and gymnosperm
C. The red algae usually reproduces vegetatively by fragmentation
D. Fusion of two gametes of similar size takes place as in species of Eudorina

Answer

To solve the question "Which of the following is an incorrect statement?", we will analyze each statement provided in the options and determine their correctness step by step.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- **Statement:** Brown algae has chlorophyll C and fucoxanthin.
- **Analysis:** Brown algae (Phaeophyceae) contain chlorophyll A, chlorophyll C, and the accessory pigment fucoxanthin. This statement is correct.

2. **Analyze the Second Statement:**
- **Statement:** Archegonia are found in Bryophyta, Pteridophyta, and Gymnosperm.
- **Analysis:** Archegonia are indeed the female reproductive structures found in Bryophyta (mosses), Pteridophyta (ferns), and Gymnosperms (conifers). This statement is also correct.

3. **Analyze the Third Statement:**
- **Statement:** Red algae usually reproduces vegetatively by fragmentation.
- **Analysis:** Red algae (Rhodophyta) can reproduce vegetatively through fragmentation, and they also reproduce sexually with non-motile gametes. This statement is correct.

4. **Analyze the Fourth Statement:**
- **Statement:** Fusion of two gametes of similar size takes place as in a species of Eudorena.
- **Analysis:** Eudorena is known to exhibit isogamous reproduction, where the gametes are of similar size. However, the statement claims that the fusion occurs with similar-sized gametes, which is misleading. In isogamous species, the gametes are indeed similar in size, but the context of the statement may imply a misunderstanding of the reproductive process. Thus, this statement is incorrect.

### Conclusion:
The incorrect statement is the fourth one: "Fusion of two gametes of similar size takes place as in a species of Eudorena."

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