Question

Heterocysts are found in certain

• A. Phaeophyceae
• B. Rhodophyceae
• C. Cyanophyceae
• D. Chlorophyceae

Answer 1

The correct option is C

Cyanophyceae

The correct option is C

Explanation for the correct option:

1. Cyanobacteria/Cyanophyceae include Anabaena and Nostoc.
2. They are capable of repairing nitrogen from the atmosphere.
3. They break down nitrogen and produce ammonia.
4. Heterocysts that specialize in nitrogen-fixing are among them.
5. They have nitrogenase enzymes.
6. Nitrogenase is deactivated by oxygen.
7. As a result of this, the heterocyst creates a micro anaerobic environment.

Explanation of the incorrect option:

Option A:

Brown algae (plural: alga) are a vast category of multicellular algae that include numerous seaweeds found in cooler waters in the Northern Hemisphere.

Option B:

The Rhodophyceae family (red algae) is a type of marine algae that is mostly red in colour and has a filamentous or membranous structure.

Option D:

A group of algae (division Chlorophyta) is defined primarily by their bright green hue, with their chlorophyll veiled or altered little or not at all by other pigments.

Final answer: Heterocysts are found in certain Cyanophyceae.