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I. Read the text and find out the role of agriculture in human life.

 

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UNIT 1

Wordlist

1. branch

2. to supply

3.animal husbandry

4. crop production

5. to harvest

6. grain crop

7. to obtain

8. favourable

9. quality

10. livestock '

11. manure ,

12. fertility

 

I. Read the text and find out the role of agriculture in human life.

WHAT IS AGRICULTURE?

Agriculture is an important branch of economy. Economic growth of any country depends on the development of agriculture. Agriculture supplies people with food and clothing and industry with raw materials. We do not know when people began to grow crops. It was many thousand years ago. Now crop production and animal husbandry are highly developed branches of agriculture. Crop production is the practice of growing and harvesting crops. The most important crops grown by man are grain crops, vegetables and grasses. In order to obtain high yields crops are grown under favourable soil and climatic conditions. Farm mechanization helps farmers obtain the highest yields of good quality. Animal husbandry is a branch of agriculture including the breeding of farm animals and their use. Farm animals are highly important sources of food for man. They are kept for the production of meat, milk, and eggs. Many crops grown by man are used in feeding livestock. At the same time manure produced by farm animals is an important source for the maintenance of soil fertility. Applying manure, farmers improve the physical condition of the soil. Thus, crop production and animal husbandry are closely connected with each other.

 

II. Put these questions into the correct order and answer them.

Model : is/what/livestock/in/feeding/use

What is used in feeding livestock?

1. agriculture/an/economy/is/important/branch/of

2. growth/country/does/depend/economic/any/of/what

3. begin/when/people/crops/grow/to/did

4. are/developed/agriculture/of/highly/branches

5. consist/important/do/crops/what/of

6. animals/what/farm/for/kept/are

7. improve/how/farmers/of/physical/soil/do/the/condition

III. The following sentences have mistakes. Correct them.

1. Agriculture an important branch of economy.

2. Economic growth of any country depend the development of agriculture.

3. Agriculture supply people food and clothing and industry with raw materials.

4. It is many thousand years ago.

5. Crop production and animal husbandry is highly developed branches of agriculture.

6. The most important crops grown with man are grain crops.

IV. Put a word from the box in the correct place to complete the following sentences.

Branch, food and clothing, animal husbandry, to obtain, breeding, livestock, manure

1. Many crops grown by man are used in feeding

2. Applying , farmers improve the physical condition of the soil.

3. Crop production and are main branches of agriculture.

4. Animal husbandry is a branch of agriculture including the of farm animals and their use.

5. In order high yields crops are grown under favourable soil and climatic conditions.

6. Agriculture is an important of economy.

7. Agriculture supplies people with

V. Translate the text using the dictionary and write questions about the underlined information.

 

Agriculture is carried out for a great variety of purposes, but most of them are associated with obtaining products. The main products may be described as food, fiber or raw materials for industrial use.

The main purpose of agriculture is the satisfaction of human needs. Human needs include individual needs and national ones, which are closely interrelated.

If the agricultural products generated by the farm are entirely used by the farmer's family such farm is called a subsistence farm. Historically as the subsistence farms became more productive they began to exchange and later to sell a part of their products.

The individual farms generate the agricultural products for internal consumption and for sale. Resources, which are used for internal consumption, include food, feed for animals, materials, fuel. The second and the third national needs can be satisfied only by market oriented farming but not by the subsistence farming.

 

GRAMMAR EXERCISES

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

 

Model: Agriculture is an important branch of economy.

a) Is agriculture an important branch of economy?

b) Why is agriculture an important branch of economy?

c) Agriculture is an important branch of economy, isnt it?

d) Is agriculture or industry an important branch of economy?

 

1) Economic growth of any country depends on the development of agriculture.

2) Agriculture supplies people with food and clothing and industry with raw materials.

3) Now crop production and animal husbandry are highly developed branches of agriculture.

4) Crop production is the practice of growing and harvesting crops.

5) Farm mechanization helps farmers obtain the highest yields of good quality.

6) Farm animals are highly important sources of food for man.

7) Applying manure, farmers improve the physical condition of the soil.

 

II. Use the verbs in brackets in the Present, Past or Future Simple.

 

1. Economic growth of any country (to depend) on the development of agriculture. 2. Agriculture (to supply) people with more food and clothing and industry with raw materials next year.3. It (to be) many thousand years ago.4. Now crop production and animal husbandry (to be) highly developed branches of agriculture. 5. Farm mechanization (to help) farmers obtain the highest yields of good quality last year. 6. Farm animals (to be) highly important sources of food for man.7. Applying manure, farmers (to improve) the physical condition of the soil next year.

 

III. Make the sentences of the exercise II negative.

Wordlist

 

 

1. to devote

2. drugs

3. descriptions

4. to expande

5. plant breeding

6. horticulture

7. ornamental plants

8. field crops

9. distinction

10. precise

11. forestry

12. recreation ,

13. timber

14. reforestation

15. tillage

16. crop rotation

17. breeding , ,

18. weed control

19. pasture

 

I. Read the text and find out the place of agronomy between other practical aspects of botany

 

BOTANY AND AGRONOMY

Botany, science devoted to the study of plants. Botany, microbiology, and zoology together compose the science of biology. Mans earliest concern with plants was with their practical uses, i.e., for fuel, clothing, shelter, and, particularly, food and drugs. The establishment of botany as an intellectual science came in classical times. In the 4th cent. D.C., Aristotel and his pupil Theophrastus worked out descriptions and principles of plant types and functions that remained the prototype for botanical observation for 1,000 years.

Modern botany has expanded into all areas of biology, including molecular biology. Perhaps most significant was the work of Mendel in plant breeding at the middle (1859) of the 19th cent., from which grew the science of genetics. The various practical aspects of experimental botany have developed into specific scientific disciplines (e.g. agriculture, agronomy, horticulture, and forestry).

Horticulture [Lat. Hortus=garden], science and art of gardening and of cultivating fruits, vegetables, flowers, and ornamental plants. Horticulture generally refers to small-scale gardening, and agriculture to the growing of field crops, usually on a large scale, although the distinction is not always precise (for example, market gardening could be classed either way).

Forestry, the management of forest lands for wood, water, wildlife, forage, and recreation. Because the major economic importance of the forest lies in wood and wood products, forestry has been chiefly concerned with timber management, especially reforestation, maintenance of the extant forest stands at prime condition, and fire control.

Agronomy, branch of agriculture dealing with various physical and biological factors- including soil management, tillage, crop rotation, breeding, weed control, and climate- related to crop production. Agronomy commonly refers to field crops, e.g. wheat, rice, corn, sorghum, soybean, cotton, as well as pasture, sugar, and forage crops; while horticulture is concerned with fruits, vegetables, flowers, and ornamental plants; forestry with forest trees; and agroforestry, with mixtures of trees with other crops.

 

II. Answer the following questions:

1. What does the botany study?

2. When did the establishment of botany as a science come?

3. What does the horticulture study?

5. What is the difference between horticulture and agronomy?

 

IV. Translate into English.

 

1. , . 2., . 3. . 4. 쳿, . 5. . 6. , , , , , .

Wordlist

1. ordination

2. theories of heredity

3. pea pod plants

4. trait , ,

 

GREGOR MENDEL

1822 - 1884

Gregor Johann Mendel was born on July 22, 1822, in Heizendorf, Austria. He was the only son of a peasant farmer. In 1843 he began studying at the St. Thomas Monastery of the Augustinian Order in Bruno. He was ordained into the priesthood in August of 1847. After his ordination, Mendel was assigned to pastoral duties, but it soon became apparent that he was more suited to teaching.

In 1849, he was assigned to a secondary school. It was there that he took the qualifying examination for teacher certification and failed. In 1851 he entered the University of Vienna to train to be a teacher of Mathematics and Biology. It was at the University of Vienna that he developed his skills as a researcher, which he utilized later in his life. Mendel returned to teaching in Bruno in 1854. Two years later he again attempted the state certification examination. He became quite ill, perhaps as a result of severe debilitating test anxiety, and he withdrew. He did attempt to take the examination again, but returned to Bruno in 1856 where he continued to teach part-time. Toward the end of his life, in 1868, Mendel was promoted in the monastery to Abbot. He died on January 6, 1884.

During the middle of Mendel's life, Mendel did groundbreaking work into the theories of heredity. Using simple pea pod plants, Mendel studied seven basic characteristics of the pea pod plants. By tracing these characteristics, Mendel discovered three basic laws, which governed the passage of a trait from one member of a species to another member of the same species.

The first law states that the sex cells of a plant may contain two different traits, but not both of those traits. The second law stated that characteristics are inherited independently from another. The third theory states that each inherited characteristic is determined by two hereditary factors (known more recently as genes), one from each parent, which decides whether a gene is dominant or recessive. In other words, if a seed gene is recessive, it will not show up within the plant, however, the dominant trait will. Mendel's work and theories, later became the basis for the study of modern genetics, and are still recognized and used today.

GRAMMAR EXERCISES

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

 

Model: Gregor Johann Mendel was born on July 22, 1822.

a) Was Gregor Johann Mendel born on July 22, 1822?

b) When was Gregor Johann Mendel born on July 22, 1822?

c) Gregor Johann Mendel was born on July 22, 1822, wasnt he?

d) Was Gregor Johann Mendel born on July 22, 1822 or on June 22, 1822?

1) In 1851 he entered the University of Vienna to train to be a teacher of Mathematics and Biology.

2) Mendel returned to teaching in Bruno in 1854.

3) He died on January 6, 1884.

4) Mendel did groundbreaking work into the theories of heredity.

5) Mendel studied seven basic characteristics of the pea pod plants.

6) The sex cells of a plant may contain two different traits, but not both of those traits.

7) Characteristics are inherited independently from another.

8) Each inherited characteristic is determined by two hereditary factors

 

UNIT 2

Wordlist

1. rock

2. weathering

3. solidification

4. aggregate

5. plant remains

6. decay , ,

7. uppermost () ()

8. leaching

9. tint

10. clay

11.silt

11. subsoil

12. manure

13. fertilizer

14. potash

15. peat

16. fen

17. bound

18. clod

19. crumb

20. potassium

21. sulphur

22. lime

23. boron

 

I. Read the text and answers the following questions:

 

1. What are the main stages of soil formation?

2. What are the differences between soil and subsoil?

3. What does the character of a soil depend on?

4. Call six primary elements of soil.

5. What is a role of microelements in the growth of plants?

 

THE SOIL

(part 1)

Soil Formation.Soil is produced from rock by the process of weathering and by the activities of plants, animals, and man. Primitive or igneous rocks, 1formed by the solidification of the magma in the process of the cooling of the earth consist of aggregates of mineral crystals, which are large, or small according to the rate at which cooling took place.2

The weathering of a rock is generally due to3a combination of physical and chemical actions. The weathered products of rock alone do not constitute a soil. Plants establish themselves very soon after weathering begins, 4and the mineral material thus becomes mixed with plant remains. These remains, in the process of decay, form an addition to the products of rock weathering. Soil is therefore a mixture of organic and inorganic material containing a large and complex population of living things.

The general character of a soil depends to a considerable extent on the nature of the parent material.5Thus a coarse-grained sandstone6will generally produce a sandy soil, and a stratum of shale7a"heavy" soil.

Soil and Subsoil.Natural soils that have been long undisturbed are composed of horizons. Soil scientists distinguish three main horizons the uppermost (A), from which material has been removed by leaching; the second (B), in which has been deposited some of the material removed from (A); and the third(), which consists of the parent material, e.g.2 the partly disintegrated rock.

The top soil is dark because of its high content of decaying vegetable matter (humus) while the subsoil varies from reddish or yellowish to a pale gray tint. Another usual difference is that the top soil is coarser grained8than the subsoil, the difference being caused by the washing down of a proportion of the finer clay and silt particles.

In general, 9the top soil will be richer in nitrogen (10)and phosphate than the subsoil, since manures and fertilizers are largely held in the former,11 butthe subsoil may frequently contain more potash.

Soil Particles.Typical soils (excepting peats and black fen types) are composed largely of particles and fragments of mineral matter. We must remember that these particles are not all free one from another12 indeed it is obvious that they are often bound together to form clods or crumbs. Nevertheless the character of a soil depends very much upon the sizes of the particles of which it is composed.

An important distinction is to be drawn between sand and silt on the one hand and clay on the other. The coarser fractions in general form the "skeleton" of the soil.

Primary elements.13Of the eleven essential elements obtained from the soil by plants, six are used in relatively large quantities.

They are nitrogen, phosphorus, potassium, calcium, magnesium and sulphur. Because they are used by plants in relatively large amounts they are sometimes called the primary elements. Plant growth may be retarded because these elements are lacking in the soil,14 because they become available too slow, or because they are not balanced by other nutrients.15This is very often true with nitrogen.16

When nitrogen, phosphorus and potassium are artificially applied to the soil, they are usually added as farm manure and especially as commercial fertilizers. Therefore, they are often called fertilizer elements.In the same way calcium and magnesium are applied as lime and are called lime elements. Sulphur usually goes into the soil as an incidental ingredient of such fertilizers as farm manure, superphosphate, and sulphate of ammonia.

Microelements.The other nutrient elements (iron, manganese, copper, zinc and boron) are used by higher plants in very small amounts and therefore are sometimes called microelements. These elements are just as important for the growth of plants as the primary elements.

Notes

 

1.primitive or igneous rocks

2. according to the rate at which cooling took place ,

3. is generally due to ... dueto ,

4. Plants establish themselves very soon after weathering begins

5. parent material

6. coarse-grained sandstone

7. a stratum of shale

8. the top soil is coarser grained

9. in general

10. be richer in nitrogen... ...

11. are largely held in the former ( )

12. are not all free one from another

13. primary elements ()

14. because these elements are lacking in the soil

15. because they are not balanced by other nutrients

16. this is very often true with nitrogen

 

GRAMMAR EXERCISES

Wordlist

 

1. colloidal residue

2. soil texture , ,

3. to impart

4. sponge

5. porosity

THE SOIL

(part 2)

 

Physical Properties of Soils.Soils are classified and mapped generally on the basis of physical characteristics which the surveyors can recognize by visual inspection. Many of the important chemical and biological properties are reflected by the physical properties of the soil. Furthermore, the physical properties of soils determine to a large extent1their productive capacity. The aeration and moisture relations, as well as area of root penetration, are determined largely by the physical makeup of soil profile.

Some of the physical properties are: texture, structure, porosity, colour and temperature relations.

Soil Texture.Texture refers to size of soil particles. Based on2size of soil particles there are three fractions: sand, silt and clay.

The sand fraction is further divided into five groups, resulting in a total of seven size groups. The seven groups are designated as seven soil separates.

Fraction Soil Separate

Sand Fine gravel

Coarse sand Medium sand Fine sand Very fine sand

Silt Silt

Clay Clay

 

The determination of the proportionate amounts of sand, silt and clay is called mechanical analysis. There are two laboratory methods of analysis. Both methods are based on the determination of the settling velocity of suspended particles in water.

The coarse materials settle rapidly, while the fine materials settle slowly.

Humus.True humus which consists of the colloidal residue of organic matter has great effects on soil texture and fertility.

Whenever it is present in considerable quantity it imparts its black or dark-brown colour to the soil, and since dark-coloured materials absorb more of the sun's heat than light-coloured ones, its presence tends to raise the soil temperature. Moreover, in well-aerated3soils humus is constantly undergoing oxidation,4with liberation of simple compounds of nitrogen5which can be taken up by plant roots. Most important is the fact that humus has many of the properties of mineral colloids it increases the soil's power of retaining moisture and it absorbs and holds plant nutrient substances. When organic matter is added to light soils the resulting humus6tends to bind the mineral particles into crumbs which absorb and hold water like miniature sponges.

It has already been noted that "raw" humus7in the absence of lime imparts to the soil a strongly acid reaction which is unfavourable to the growth of most higher plants.

If the humus content is to be maintained at a high level, repeated applications8of organic matter have to be made.

The means of maintaining the humus content include the use of manure and composts and the ploughing in of "green manuring" crops.9

 

 

Notes

1. to a large extent

2.based on

3. well-aerated

4. is constantly undergoing oxidation

5. liberation of simple compounds of nitrogen

6. resulting humus ,

7. "raw" humus

8. repeated applications

9. the ploughing in of "green manuring" crops

 

Answer the questions.

1. What does successful farming mean?

2.What are the important points of successful farming?

3.What are the factors that makeup the soil fertility?

4.What does the cultivated soil provide?

5.Do the legumes improve the soil fertility?

6.What must we know before growing the plants?

7.What is necessary to do to obtain a high yield of good quality crop?

 

VIII. Retell the text.

 

 

GRAMMAR EXERCISES

I. Translate sentences paying attention to the words: due to, to be due to ...:

 

1. Soil formation is due to the process of weathering rock and to the activity of plants, animals, and man. 2. The weathering of a rock is generally due to a combination of physical and chemical actions. 3. The general character of a soil is partly due to the nature of the parent material. 4. The decay of organic matter is due to the activity of microorganisms, bacteria, moulds and other fungi.

 

UNIT 3

Wordlist

timberland

diversification

nutrient

legume i , ,

virgin soil , ,

treatment

deterioration

wet

neglecting

depletion

handling

fertilizer

 

I. Read the text and answers the following questions:

 

1. What is the crop rotation?

2. What is the way of returning nitrogen to the soil?

3. What is the difference between virgin soils and the soils for crops and pastures?

4. What things may contribute to the deterioration of soil structure?

5. What properties determine the agricultural quality of soils?

USES AND CARE OF SOILS

 

There has always been great variation in the quality of soils available for agriculture. In most instances, the better soils are used for crops, and the less suitable ones are kept for pastures or timberlands.

The systematic alternating of crops from field to field is known as crop rotation, which is one of the methods of soil conservation. A good rotation system consists of adjusting the crop arrangement to the physical nature of the land and, in the same time, maintaining a balanced economic farming programme. Rotation implies the growing of more than one crop on a farm. In other words, rotation and diversification go hand in hand.

Since no two crops make identical demands on the soil, one crop may require excessive amounts of a given nutrient, which another crop may be able to supply. For example, legumes return nitrogen to the soil, but most other crops require more nitrogen than the soil can normally supply.

Time makes little change in virgin soils. But when soils are used for crops or pasture, the balance that nature has given them is upset in various ways and to varying degrees. Changes in the nature of soils cannot be avoided as they are put to diverse uses. These changes may result in improvement in productivity. Frequently, however, soil use results in soil damage and decreased yields. Thus careful treatment of soils in ways that will keep them productive through continuous use is the aim of every good agricultural programme.

Improper use may result in the deterioration of soil structure; several things may contribute to this deterioration, including: plowing when soil is too wet; failure to return organic matter; unwise use or lack of lime; neglecting to rotate crops. An even more serious and widespread kind of soil damage is the loss of essential plant nutrients. This may result from continuous growing of the same crop and from failing to fertilize it properly. Still another serious cause of depletion in most soils is known to be the loss of organic matter.

Properties that determine the agricultural quality of soils include: 1) ability to produce high crop yields under good management and careful handling; 2) the ease with which they can be used profitably; 3) the amount and kind of care they require. Good soils respond well to proper management, which involves correct cropping practices, use of fertilizers, and effective protection against damage. Without good care all crop land deteriorates with continuous use. The loss that results from improper care of good soils is greater than from improper care of poor soils, since the former are more valuable. Nevertheless, it is highly important to give the best possible care to all soils, and particularly to the best soils. This is one of the first essentials of good farming methods.

ROTATIONS

A rotation is a succession of crops usually fixed in a certain definite order. Nowadays rotations are not so fixed as before. To meet the changing conditions and the needs of the market, new crops can be introduced into rotations and changes made when and where needed.

The opposite of a rotation is to grow one crop year after year. This is known as monoculture and can lead to troubles, particularly disease. The one crop, which can be grown in this way, is grass; permanent grass, if farmed properly, can be productive for a long time.

GRAMMAR EXERCISES

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

Model: Good soils respond well to proper management.

1) Do good soils respond well to proper management?

2) What do good soils respond well to?

3) Good soils respond well to proper management, dont they?

4) Do good soils respond well to proper management or good care?

 

1. A good rotation system consists of adjusting the crop arrangement to the physical nature of the land.

2. There has always been great variation in the quality of soils available for agriculture.

3. Rotation and diversification go hand in hand.

4. Legumes return nitrogen to the soil

5. Time makes little change in virgin soils.

6. Improper soil use may result in the deterioration of soil structure.

Wordlist

inherent fertility

bulky

manure

furnish ()

amenable ,

ameliorate

farmyard ,

potassium

soluble

compound

break down

moisture-holding

capacity

drought resistance

binding effect

incorporation

base-exchange

capacity

 

APPLICATION OF FERTILIZERS

 

Fertilizer must be put into the seedbed, where it will do most good to the young plant as it grows. This is done in two ways: a) fertilizer is spread on the seed-bed before the seed is sown and usually harrowed in; b) fertilizer is put in at the same time as the seed and usually near to it in the soil. Top-dressing means putting a fertilizer onto a growing crop. It is commonly done with nitrogen fertilizers on growing grain crops such as a spring dressing of sulphate of ammonia for a crop of winter wheat. If the nitrogen had been applied in the seedbed, most of it would be washed out during the winter. Lime and plant foods in fertilizers are not all used up in the year they are applied to the land. Some of the value is left over for a year or more and helps later crops.

GRAMMAR EXERCISES

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

Model: Farmyard manure contains all the important nutrients.

1) Does farmyard manure contain all the important nutrients?

2) What does farmyard manure contain?

3) Farmyard manure contains all the important nutrients, doesnt it?

4) Does farmyard manure or chemical fertilizer contain all the important nutrients?

 

1. Soil must have a suitable reaction in the chemical sense.

2. Soil must contain no substances toxic to growth.

3. The potassium present is readily soluble and immediately available.

4. Applications of manure can have a beneficial action upon the physical properties.

5. Soil colour will be darkened by the incorporation of humus.

UNIT 4

Wordlist

 

plant

animal

cell

unicellular organisms

protozoan ()

evolve ,

tissue

DNA

prokaryote

segregate ,

nucleus

eukaryote

RNA

adenosine triphosphate

double layer

plant kingdom

algae

stimuli

rigid

adult

meristem tissue

root

stem tip

bud

I. Read the text and answers the following questions:

1. What is the cell?

2. How can cells be separated?

3. What is the difference between prokaryotes and eukaryotes?

4. What are the common properties of all cells?

5. What are the main distinguishing indications between plants and animals?

CELL AND PLANT

 

Cell, in biology, the unit of structure and function of which all plants and animals are composed. The cell is the smallest unit in the living organism that is capable of integrating the essential life processes. There are many unicellular organisms, e.g., bacteria and protozoans, in which the single cell performs all life functions. In higher organisms, a division of labor has evolved in which groups of cells have differentiated into specialized tissues, which in turn are grouped into organs and organ systems.

Cells can be separated into two major groupsprokaryotes, cells whose DNA is not segregated within a well-defined nucleus surrounded by a membranous nuclear envelope, and eukaryotes , those with a membrane-enveloped nucleus. The bacteria are prokaryotes. They are smaller in size and simpler in internal structure than eukaryotes and are believed to have evolved much earlier. All organisms other than bacteria consist of one or more eukaryotic cells.

All cells share a number of common properties: they store information in genes made of DNA; they use proteins as their main structural material; they synthesize proteins in the cell's ribosomes using the information encoded in the DNA and mobilized by means of RNA; they use adenosine triphosphate as the means of transferring energy for the cell's internal processes; and they are enclosed by a cell membrane, composed of proteins and a double layer of lipid molecules, that controls the flow of materials into and out of the cell.

Any organism of the plant kingdom, as opposed to one of the animal kingdom. A plant may be microscopic in size and simple in structure, as are certain one-celled algae, or a gigantic, many-celled complex system, such as a tree.

Plants are generally distinguished from animals in that they possess chlorophyll, are usually fixed in one place, have no nervous system or sensory organs and hence respond slowly to stimuli, and have rigid supporting cell walls containing cellulose. In addition, plants grow continually throughout life and have no maximum size or characteristic form in the adult, as do animals. In higher plants the meristem tissues in the root and stem tips, in the buds, and in the cambium are areas of active growth. Plants also differ from animals in the internal structure of the cell and in certain details of reproduction.

GRAMMAR EXERCISES

 

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

 

Model: Plants grow continually throughout life.

1) Do plants grow continually throughout life?

2) How do plants grow?

3) Plants grow continually throughout life, dont they?

4) Do plants grow continually throughout life or during some periods of their life?

 

1. The cell is the smallest unit in the living organism.

2. Cells can be separated into two major groupsprokaryotes and eukaryotes.

3.The bacteria are prokaryotes.

4. All organisms other than bacteria consist of one or more eukaryotic cells.

5. Cells store information in genes made of DNA.

6. Cells use proteins as their main structural material.

 

Wordlist

 

fossil

comparison

nucleic acid sequence -

clarify

thallophytes ,

()

embryo

alternating ,

undifferentiated thallus

,

lacking : , .:

stem

leave

fungi , ,

embryophyte

vascular tissues i

moist

xylem

phloem ,

inhabit

species , , , ,

club moss

horsetail

extinct

fern

cone-bearing gymnosperms

angiosperms

true flowering plants

seed

spermatophyte

perennial

order

conifer () ()

ginkgo

cycad

monocotyledonous plants

cotyledon - -

scattered

vascular bundles

vein

dicotyledonous plants

cattail

tiny herbs

ornamental

 

I. Read the text and answers the following questions:

 

1. How can we clarify the relationships among plants nowadays?

2. What large groups was the plant kingdom traditionally divided into?

3. What is the common and different between thallophytes and embryophytes?

4. What groups are embryophytes composed of?

5. What are the main parts of the vascular plants?

THE PLANT KINGDOM

 

The systems of classification of the plant kingdom vary in naming and placing the larger categories because there is little reliable fossil evidence, as there is in the case of animals, to establish the true evolutionary relationships of and distances between these groups. However, comparisons of nucleic acid sequences in plants are now serving to clarify such relationships among plants as well as other organisms.

The plant kingdom traditionally was divided into two large groups, or subkingdoms, based chiefly on reproductive structure. These are the thallophytes, which do not form embryos, and the embryophytes, which do. All embryophytes and most thallophytes have a life cycle in which there are two alternating generations. The plant form of the thallophytes is an undifferentiated thalluslacking true roots, stems, and leaves. The thallophytes are composed of more than 10 divisions of algae and fungi. The embryophytes are composed of two groups: the bryophytes, which have no vascular tissues, and a group consisting of seven divisions of plants that do have vascular tissues.

The vascular plants have true roots, stems, and leaves and a well-developed vascular system composed of xylem and phloem for transporting water and food throughout the plant; they are therefore able to inhabit land. Three of the divisions of the vascular plants are currently represented by only a very few species. They are the Psilotophyta, with only three living species; the Lycopodiophyta (club mosses); and the Equisetophyta (horsetails). All the plants of a fourth subdivision, the Rhyniophyta, are extinct. The remaining divisions include the dominant vegetation of the earth today: the ferns, the cone-bearing gymnosperms, and the angiosperms, or true flowering plants. The latter two classes, because they both bear seeds, are often collectively called spermatophytes, or seed plants.

The gymnosperms are all woody perennial plants and include several orders, of which most important are the conifer, the ginkgo, and the cycad. The angiosperms are separated into the monocotyledonous plantsusually with one cotyledon per seed, scattered vascular bundles in the stem, little or no cambium, and parallel veins in the leafand the dicotyledonous plantswhich as a rule have two cotyledons per seed, cylindrical vascular bundles in a regular pattern, a cambium, and net-veined leaves. There are some 50,000 species of monocotyledon, including the grasses (e.g., bamboo and such cereals as corn, rice, and wheat), cattails, lilies, bananas, and orchids. The dicotyledons contain nearly 200,000 species of plant, from tiny herbs to great trees; this enormously varied group includes the majority of plants cultivated as ornamentals and for vegetables and fruit.

KINGDOMS

BACTERIA  
? Algae Protozoans
FUNGI Zygomycota Basidiomycota
? Nonvascular Seedless Bryophyta  
Vascular Seedless Pretophyta
Vascular Seed Gymnosperms Coniferophyta
Ginkgophyta
? Anthophyta
Monocotyledones
?
ANIMALIA  

X. Read the text without the dictionary and answer the following questions:

1. What plants were the first on our planet?

2. Why are ferns, club-mosses, and horsetails called as the seedless vascular plants?

3. What is the difference between gymnosperms and angiosperms?

4. What does "Gymnos" mean?

5. What does angio mean?

6. What main parts are seeds composed of?

7. What are the main groups of angiosperms?

 

PLANT EVOLUTION

 

The first terrestrial plants to evolve, over 400 million years ago during the Paleozoic, were Bryophytes such as mosses (o). These show some of the first adaptations to land, including a waxy cuticle and enclosed gametangia (structures which produce gametes ( ) for sexual reproduction). All other plants developed vascular tissue, which transports water and nutrients throughout the plant.

The seedless vascular plantsinclude ferns (), club-mosses (), and horsetails (). They reproduce by spores and have vascular tissues. All other plants developed seeds for reproduction.

The gymnosperms include conifers and cycads. Gymnosperms have vascular tissue and reproduce with seeds. "Gymnos" means "naked" in Greek, and the seeds of gymnosperms do not have a special chamber enclosing them, in contrast with the angiosperms. Christmas trees, which are usually spruce () or pine (pine is the "no-shed" Christmas tree), are conifers.

The angiosperms, or flowering plants, include most obvious plants, from an oak () tree to the pansies (). Angio means container in Greek, and the angiosperms have developed flowers around the protective chamber called the ovary which, when the egg is fertilized, produces the seed. Seeds are composed of an embryo together with a food supply for its early development, inside a protective seed coat. Seed coats protect the embryo from threats such as drought and fire, and some species seeds can remain viable (able to develop) for many years in the soil.

Angiosperms also have vascular tissue. This group, which numbers about 235,000 species, is further divided into monocots, such as daffodils, grass, and tropical palm trees, and dicots (or eudichots), such as beech trees, violets, and daisies.

 

Wordlist

shoot system

root system

bud

stem

tuber

rhizome

meristem ,

tissue

dermal

ground

vascular ,

waxy cuticle

General Plant Organization

A plant has two organ systems: 1) the shoot system, and 2) the root system. The shoot system is above ground and includes the organs such as leaves, buds, stems, flowers (if the plant has any), and fruits (if the plant has any). The root system includes those parts of the plant below ground, such as the roots, tubers, and rhizomes.

Plant cells are formed at meristems, and then develop into cell types which are grouped into tissues. Plants have only three tissue types: 1) Dermal; 2)Ground; and 3) Vascular. Dermal tissue covers the outer surface of herbaceous plants. Dermal tissue is composed of epidermal cells, closely packed cells that secrete a waxy cuticle that aids in the prevention of water loss. The ground tissue comprises the bulk of the primary plant body. Vascular tissue transports food, water, hormones and minerals within the plant.

Major organ systems of the plant body.

 

ROOT SYSTEM

Wordlist

ascending axis

dissolve

anchor

tap-root system

diffuse

slender

parsnip

dandelion

alfalfa

ramified

tip

meristematic tissue

thrust

split

Root, in botany, the descending axis of a plant, as contrasted with the stem, the ascending axis. In most plants the root is underground. Roots function to absorb water and dissolved minerals from the soil, to transport water and nutrients, to anchor the plant, and often to store food.

There are two main types of root system: the tap-root system, in which there is a main primary root larger than the other branching roots; and the diffuse (or fibrous) root system, in which there are many slender roots with numerous smaller root branches. Tap roots are characteristic of most trees and of many other plants, including the carrot, parsnip, radish, beet, and dandelion. The grasses (e.g., corn, rye, and alfalfa) have diffuse roots; in the sweet potato some of the larger fibrous roots swell to store foodalthough these should not be confused with the tuber of the Irish potato, which is a modified underground stem.

Root systems often far exceed in mass the aboveground portions of the plant: alfalfa roots sometimes reach 40 ft (12 m) in length, and the combined length of all the roots of a mature rye plant has been measured at 612 km. These ramified root systems are important agents in preventing soil erosion. Roots grow primarily in length; only the older roots may develop a cambium layer that increases their diameter.

Protecting the constantly growing tip of the root is a cap of cells that break off as the root probes through the soil; they are replaced by new cells from a layer of meristematic tissue just behind them. Although root hairs are less than 1/3 in. (.84 cm) long, their great number enables the plant to collect enormous quantities of water, most of which is promptly lost into the air by trans

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