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Essential English for Biology Students.doc
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A typical animal cell

The structure of a typical animal cell:

  • the cell has a cell surface membrane which encloses the cell contents

  • the contents consist of a central ball-shaped nucleus surrounded by material called cytoplasm

  • the nucleus contains a fibrous material called chromatin

  • this condenses to form chromosomes during cell division

  • chromatin contains DNA, the material which controls the various activities inside the cell

  • scattered within the cytoplasm are mitochondria, small rod-like structures. They have been described as the “power-houses” of the cell because they supply energy.

  • smaller dots within the cytoplasm are particles of stored food. Many consist of glycogen, which is a food storage polysaccharide.

A typical plant cell

Like an animal cell, a typical plant cell has a cell surface membrane, cytoplasm, and a nucleus. However, plant cells differ from animal cells in several ways:

  • most plant cells have a large sap-filled cavity called the vacuole. Sap is a watery fluid containing salts and sugars. The vacuole surrounded by a membrane called the tonoplast.

  • the cytoplasm contains starch grains, the food storage products of plants

  • many plant cells have chloroplasts in the cytoplasm. These contain the pigments used in photosynthesis. Chlorophyll, which is green, is the main pigment. Chloroplasts occur only in the parts of plants exposed to light – the green parts. They are absent from underground structures such as roots.

Glossary of essential terms for you to know

English term

Russian equivalent

1

cork

пробка

2

honeycomb

соты пчелиные

3

cell

клетка

4

to embody

воплощать, олицетворять

5

to enclose

окружать

6

contents

содержимое

7

surface

поверхность

8

membrane

мембрана

9

nucleus

ядро

10

to surround

окружать

11

cytoplasm

цитоплазма

12

fibrous

волокнистый, фиброзный

13

division

деление

14

to scatter

разбрасывать, рассыпать

15

to supply

обеспечивать, снабжать

16

storage

хранение

17

sap

сок растения

18

cavity

полость

19

starch

крахмал

20

root

корень

21

compound

сложный

22

to observe

наблюдать

23

to examine

исследовать

24

feature

черта

25

suitable

подходящий

26

existence

существование

27

fluid

жидкость

28

grain

зерно

Your Essential Assignments

I. Quick check

1. Briefly state the main concept of the cell theory.

2. List the features:

a) that only animal cells have

b) that only plant cells have

c) that both animal and plant cells have.

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