Working with Protazoa

Working with Protozoa

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Working with Protozoa
Protozoa are among the most fascinating organisms that can be studied in the classroom or laboratory. The Protista kingdom has seven groups that are divided into fifteen phyla. These subdivisions show the wide range of morphology and function that demonstrate the basic properties of living matter. This diversification is one of the reasons that students seem to be instantly fascinated by the study of these organisms. The different phyla are distinguished from one another by such features as structure, means of locomotion, and formation of spores, although the locomotor organelles are the primary distinguishing feature. There are three main locomotor organelles found in the different classes of protozoa, and they are pseudopodia, cilia, and flagella. A pseudopodium is generally not considered to be a separate organelle, but rather is formed by the extension of protoplasm outward from the main body. The pseudopodium then anchors itself while the rest of the organism flows into the pseudopodium. Pseudopodia are also used to surround and ingest food particles. Unlike the pseudopodium, both cilia and flagella are considered to be discrete organelles. Both structures move the organism by beating in a rhythmic or random pattern, and structurally are almost the same. The main difference between these two organelles is that flagella are usually found singly or in small groups near the leading end of the body, while cilia are found in large numbers in longitudinal rows on the body or near the mouth. Most protozoa reproduce through a process called fission, which is simply the organism dividing into two cells by mitosis. In addition to fission, some ciliates are able to reproduce sexually through conjugation. In this process two cells unite and exchange genetic material.

Collection of protozoa is possible from almost any conceivable habitat....