Lecture Listen to part of a lecture in a biology class. Then put the major points in the same order as the lecture. Major Points

Lecture
Listen to part of a lecture in a biology class.
The protozoans, minute aquatic creatures, each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. The very name protozoan indicates the scientific understanding of the animals. Proto means "first" or "primitive" and zoa refers to the animal.
They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails that they use to propel themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.
In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.
So all of this seems very straightforward to this point, but now we are going to complicate the picture. Chlorophyll, which is the green substance in plants, is also found in the bodies of some protozoans, enabling them to make at least some of their own food from water and carbon dioxide. Sounds like photosynthesis, doesn’t it? But protozoans are animals, right? And plants are the life forms that use photosynthesis. Okay. Well protozoans are not considered plants because, unlike pigmented plants to which some protozoans are otherwise almost identical, they don’t live on simple organic compounds. Their cells demonstrate all of the major characteristics of the cells of higher animals, such as eating, breathing, and reproducing.
Now many species of protozoans collect into colonies, physically connected to one another and responding uniformly to outside stimuli. Current research into this phenomenon along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as technology improves methods of observation, better models of classification of these simple single cells will be proposed.