The digestion of food in all protozoan protists is .......

Explanation

**Step-by-Step Solution:**

1. **Understanding Protozoan Protists**: Protozoans are single-celled organisms that belong to the kingdom Protista. They are often found in aquatic environments and can be free-living or parasitic.

2. **Digestion Process in Protozoans**: In protozoan protists, the digestion of food occurs within specialized structures called food vacuoles. These vacuoles are membrane-bound compartments that enclose food particles.

3. **Role of Lysosomes**: Once the food is enclosed in the food vacuole, lysosomes, which are organelles containing digestive enzymes, fuse with the food vacuole. This fusion is crucial for the digestion process.

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