1. What is the basic material of all living systems?
2. What elements does living matter consist of?
3 Are plants and animals similar?
4 What are the differences between them?
1.18 Work in groups. Read the text and say what new information about plants and animals you have got from it:
Biology is the study of living things. In studying them we learn the relations of plants and animals to one another, with the world about them and how we can control them. Biology is commonly divided into two branches – botany and zoology. Both animal and plant life is continually changing and there are great differences and likenesses between them.
All organisms are capable of responding to changes in the environment by reacting to external stimuli. In animals this coordination and response to stimuli are accomplished by sense organs and the endocrine and nervous systems.
Plants lack a nervous system and specific sense organs but they respond to external stimuli and chemical coordination in somewhat analogous to that regulated by the endocrine system of animals.
Both plants and animals have hormones. Thus substances are produced in one part of the organism and in very small amounts influence specific physiological processes when transported to another part of the organism. Plant hormones, however, are not produced in specific glands as animal hormones are, and they differ chemically from the hormones of animals, being in general simpler substances. Other substances, which act like hormones but are not known to be produced by the plant, are called plant regulators. The study of plant hormones and these synthetic substances is one of active fields of plant physiological research, and their use in agriculture has become very important.
Complete the gaps in the following text with the words from
|external, apparent, chemical, varied, variety, unit, animal|
In (1)... appearance plants are usually green. Some plants have (2)... and colourful flowers and others have no (3)... blossoms. Among animals there is great (4)... of sizes, shapes and colours. The basic difference between plants and animals lays in the (5)... of structure and function of each, namely, the cell. Plant cells have a cell wall, which is actually non-living in (6)... nature. (7)... cells do not have this.
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