Heterocysts are present in bacteria/cyanobacteria.

Explanation

**Step-by-Step Solution:**

1. **Identify the Organisms in Question**: The question asks whether heterocysts are present in bacteria or cyanobacteria.

2. **Define Heterocysts**: Heterocysts are specialized cells that are found in certain types of cyanobacteria. They are not found in typical bacteria.

3. **Characteristics of Heterocysts**: Heterocysts are colorless because they lack chlorophyll. This is an important characteristic that distinguishes them from other cells in cyanobacteria that contain chlorophyll.

...