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III. Answer the following questions.

1. What are roots functions?

2. What two main types of root system do you know?

3. How do roots grow?

4. What is a function of the root tip?

IV. Complete each sentence with a word or phrase from the text.

1. Roots grow primarily

2. in which there is a main primary root larger than the other branching roots

3. the descending axis of a plant, as contrasted with the stem, the ascending axis.

4. comprises the bulk of the primary plant body.

5. Plant cells are formed at meristems, and then develop into

6. is above ground and includes the organs such as leaves, buds, stems, flowers

7. includes those parts of the plant below ground.

8. covers the outer surface of herbaceous plants.

9. transports food, water, hormones and minerals within the plant.

10. to absorb water and dissolved minerals from the soil, to anchor the plant, and often to store food.

11. in which there are many slender roots with numerous smaller root branches.

12. In spite of their slenderness and delicate structure, the spiraling forward thrust of the root tips and the pressure of their expanding cells is sufficient

V. In the second column select the words and the word combinations equivalent to those in the first one.

 

1.split 1.

2.ramified 2.

3.dissolve 3.

4.stem 4.

5.root system 5.,

6.shoot system 6.

7.bud 7.

8.vascular 8.

9.tap-root system 9.

10.tip 10.

 

VI. Name a word or a word combination, which is not a part of the logical group.

1. Shoot system, root system, cell.

2. Dermal, Ground, Vascular, dandelion.

3. Tap-root system, diffuse (or fibrous) root system, taxonomy.

 

VII. The following sentences have mistakes. Correct them.

 

1. Protecting the constantly growing tip of the root is a head of cells.

2. Tap roots are characteristic of most grasses.

3. Roots function to dissolve minerals from the soil, to anchor the plant, and often to store water.

4. Plants have only two tissue types: 1) Dermal; 2) Ground.

5. The shoot system is under ground and includes the organs such as leaves, buds, stems, flowers (if the plant has any), and fruits and vegetables (if the plant has any).

6. The shoot system includes those parts of the plant below ground, such as the roots, tubers, and rhizomes.

7. Vascular tissue transports food, water, hormones and minerals outside the plant.

8. There are three main types of root system.

9. Roots grow primarily in width.

VIII. Fill in the blanks in the given figures, explain the main functions of root system.


IX. Translate into English.

, , .

: . , , . .

, , . .

 

X. Using the text ROOT SYSTEM describe the figures giving the main differences between two main types of root system.

GRAMMAR EXERCISES

I. Put up four questions of different types (general, special, disjunctive, alternative) to each sentence.

Model: In most plants the root is underground.

1) Is the root underground in most plants?

2) What root is in most plants?

3) In most plants the root is underground, isnt it?

4) Is the root underground or ground in most plants?

1. There are two main types of root system.

2. There is a main primary root larger than the other branching roots in the tap-root system.

3. There are many slender roots with numerous smaller root branches in the diffuse (or fibrous) root system.

4. The grasses (e.g., corn, rye, and alfalfa) have diffuse roots.

5. Roots grow primarily in length.

 

II. Put the verbs in brackets into the appropriate form and explain the usage of that form in the sentence.

1. The grasses (e.g., corn, rye, and alfalfa) (to have) diffuse roots 2. In the sweet potato some of the larger fibrous roots (to swell) to store food 3. Root systems often far (to exceed) in mass the aboveground portions of the plant. 4. These ramified root systems (to be) important agents in preventing soil erosion.

III. Make the sentences of the exercise II negative.

Wordlist

vegetative shoot

floral shoot , ,

stem

node

internode

axillary bud

apex , ,

terminal bud

apical

exposure

reproductive shoot

vegetative branch

flattened blade

petiole

I. Read the text and answer the following questions:

1. What main parts does the shoot system consist of?

2. Where is shoot growth usually concentrated?

3. What is apical domination?

4. What difference between a reproductive shoot and a vegetative branch?

5. What do leaves in general consist of?

6. How is it possible to classify plants?

SHOOT SYSTEM

The shoot system consists of vegetative shoot (stem and attached leaves) and floral shoots terminating in flowers.

STEM

A stem has an alternation of nodes (points where leaves are attached) and internodes (the stem segments between nodes) and an axillary bud (the angle formed by each leaf and the stem). Shoot growth is usually concentrated at the apex of a shoot where there is a terminal bud with developing leaves and a compact series of nodes and internodes. The terminal bud plays a part in apical dominance, inhibiting the growth of axillary buds. Apical dominance is an evolutionary adaptation that increases the plants exposure to light by concentrating resources on growing taller. To increase the exposure of the shoot system to the environment branching becomes important and under certain conditions, axillary buds begin to grow. Each bud has the potential to give rise to either a reproductive shoot (bearing flowers) or a vegetative branch.

LEAVES

Leaves are the main photosynthetic organs of most plants. They vary in form but in general consist of a flattened blade and a petiole (stalk), which joins the leaf to a node of the stem. Vascular arrangement, leaf shape and leaf placement on a stem can help to identify or classify plants.

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