Chapter 37, Problem 11STP

Summary Introduction

To explain:

The characteristics that are used to classify protists into three groups.

Introduction:

A protist is a eukaryotic organism whose cell contains a cell nucleus that is not an animal, plant or fungus. They are heterotrophic in nature that is they feed on other organisms to obtain nutrition.

Explanation of Solution

Protists are heterotrophic in nature that is they feed on other organisms to obtain nutrition. They are eukaryotic organism whose cell contains a cell nucleus that is not an animal, plant or fungus. Protists are a variety of human diseases including malaria, sleeping sickness, amoebic dysentery and trichomoniasis. The characteristics that are used to classify protists into three groups are described below-

1. Flagellated Protozoans: They possess flagella for locomotion. They may be free-living aquatics, parasites, symbionts . Zooflagellates are generally uninucleate or multinucleate.
2. Amoebid Protozoans: They develop pseudopodia that are temporary protoplasmic outgrowths. These are used for locomotion and engulfing food articles. Sarcodines are mostly free-living, found in fresh water and sea water and on damp soil.
3. Ciliated Protozoans: Ciliates are protozoan protists. They develop a number of cilia during a part or whole of the life cycle. They use cilia for locomotion and driving food.

Conclusion

Protists are a variety of human diseases including malaria, sleeping sickness, amoebic dysentery and trichomoniasis. They survive in both marine and terrestrial environments.