3. Answer the following questions on the text in written form.

1. Where does the Common Amoeba live?

2. What is the structure of the amoeba?

3. The Amoeba takes in organic matter found in microscopic algae, doesn’t it?

4. What is used to build up the body of the Amoeba?

5. How is the unused food excreted?

6. Why does oxygen easily pass into all sections of the Amoeba’s protoplasm?

7. How do the Amoebae react to light?

8. How does the Amoeba multiply?

9. What is encyctment?

10. What is the difference between the Common Amoeba and the Dysenteriae?

4. Translate a passage into Russian in written form. Text 5 malaria parasite

Pathogenic Agent

Using the microscope scientists have been able to study the structure of human blood, which was found to consist of transparent fluid and tiny red blood corpuscles swimming therein. It is these corpuscles that make blood red. In man's lungs they combine with oxygen which they carry to all the living cells of the body. In the last century, the red blood corpuscles of patients suffering from malaria were found to contain many Amoeba-like single-celled parasites.

Having penetrated a red blood corpuscle, the parasite grows at its expense. The full-grown parasite fills the entire corpuscle and then divides into several parts, not in two as the Amoeba does. Between 8 and 12 new parasites are formed, which burst the corpuscle and penetrate the blood stream along with the toxic excreta of the mother-parasite. The action of the toxic excreta on the human body causes a severe attack of fever. As for the young parasites, they get into healthy blood corpuscles, consume them, and burst them in a couple of days.

The attacks of fever coincide with the entry of malaria parasites into the blood stream and recur regularly, in some cases every twenty-four hours, in others - at intervals of two to three days. The number of parasites in the blood keeps increasing and a tremendous number of red blood corpuscles are destroyed. If the sick person does not receive timely medical attention he may die.

Transmitting Agent

Man gets malaria parasites from the malaria-carrying Mosquito, The Mosquito bites, and the parasites are injected into the man's organism with the saliva from the insect. After a certain period attacks of malaria begin. The Mosquito gets the parasites when it bites people suffering from malaria. Inside the Mosquito, the parasites multiply rapidly. In a few days, they fill the salivary glands of the Mosquito which becomes a malaria-carrier. Mosquito eggs are laid in shallow stagnant water. Therefore malaria is widespread is marshy places, especially where the climate is warm. Previously it was called "marsh fever".

Conclusion

The specific feature of the Protozoa, that distinguishes them from all other animals, is that they are all single-celled. The rest of the animal kingdoms are multi-cellular.

The Protozoa are microscopically small. They are either barely visible to the naked eye or not visible at all. They can only live in fluids: water, blood, etc.

Their structure is so simple that it is quite possible that they belong to the most ancient group of animals to have lived on the Earth. They are economically important to man and help in maintaining balance of Nature. Many of the Protozoa serve as food for young fish and thus indirectly help to provide man with food. The compressed bodies of certain protozoa, which have shells composed of lime and other minerals, form hard layers, from which limestone is derived. Certain protozoa such as the malaria parasite live as parasites in man and other animals and are the causes of serious diseases that affect these animals.

Tasks