II. Listen to the following piece of information about cellulose. Fill in the missing words or phrases

Cellulose is the (1)____________ of the cell wall of all plant cells. In plants, cellulose is normally combined (2)____________ or gummy substances. With some exceptions among insects, true cellulose is not found (3)____________. Microorganisms in the digestive tracts of (4)____________ break down the cellulose into products that can then be absorbed. Cellulose is insoluble in (5)____________ and may be readily separated from the other (6)____________. Depending on its concentration, sulphuric acid acts on cellulose (7)____________, soluble starch, or amyloid; the last is a form of starch (8)____________ of parchment paper. When cellulose is (9)____________ and then exposed to the fumes of carbon disulfide, the solution (10)____________. Rayon and cellophane are cellulose regenerated from such solutions. (11)____________ are spun into fine filaments for the manufacture of some fabrics and are also used for (12)____________, as a substitute for glass, for the manufacture of safety glass, and as (13)____________. Cellulose ethers are used in paper sizings, adhesives, (14)____________, and (15)____________.

WRITING AND SPEAKING

Write a summary of the text “Macromolecules” in 200 words using the vocabulary of Lesson 1. Get ready to present it in class

Lesson 2

CELL AS A BASIC UNIT OF LIFE

PRE-READING TASKS

I. Answer the following questions

· What meanings of the word “cell” do you know?

· Why do you think the basic unit of life was called the cell?

· What do you know about cells as units of life?

II. Listen to the following words and practice their pronunciation

Virus; totipotent; subcellular; micrometer; algae; neuron; prokaryotic; eukaryotic; Monera; nucleus; nuclei; nucleoid; fungus; fungi; plasma membrane; cytoplasm; minute.

READING COMPREHENSION AND VOCABULARY DEVELOPMENT

I. Match each word on the left to its correct definition on the right

1) preexisting, adj 2) fusion, n 3) induce, v 4) intact, adj 5) volume, n 6) projection, n 7) interfere, v 8) remainder, n 9) enclose, v

a) to get involved in a situation where one is not wanted or needed; b) to call forth or bring about by influence or stimulation; c) the part of something that is left; the rest of; d) to surround or fence off; e) a merging of diverse, distinct, or separate elements into a unified whole; f) having no relevant component removed or destroyed; entire; uninjured; g) the amount of space occupied by a three-dimensional object as measured in cubic units; h) something that existed earlier or before; i) something that sticks out from a surface.

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II. Regard the suffixes enlisted below. What parts of speech are formed by means of these suffixes? Find the words containing such suffixes in the text. What do they mean?	\|	II. Read the following text paying attention to the highlighted words. Explain or interpret the contextual meaning of the underlined phrases

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