I. Quick check. 1. What distinguishes stems from other plant?

1. What distinguishes stems from other plant?

2. List the four functions structures?

3. How do parenchyma cells support herbaceous stems?

II. Fill in the missing words:

Term (verb)	Noun	Adjective
disperse	.......	…….
attach	.......	…….
….....	location	…….
identify	.......	…….
store	.......	…….
maintain	.......	…….
penetrate	…..	…….
.........	strength	…….
grow	........	…….
add	.......	…….

III. Use monolingual English dictionary and write down what could the words given below mean:

ground, growth, woody stem, non-woody stem, exchange, flexibility, growing season, resist, bundle.

IV. Find English equivalents to the following word combinations:

N	Russian term	English equivalent
1. 1	наземные растения
2.	получать оптимальную экспозицию к свету
3.	удерживать цветы и плоды
4.	эффективное опыление
5.	рассеивание семян
6.	заменять умершие клетки
7.	хранить (запасать) воду, питательные вещества
8.	трудно опознать (идентифицировать)
9.	эпидермис заменяется корой
10.	внутренние части стебля
11.	принимать форму пучков (узлов)
12.	придавать стеблю прочность и гибкость

V. Give Russian equivalents to the following English terms:

N	English term	Russian equivalent
	foremost organs of support
	attachment site of a leaf
	most stems point upward
	easily distinguished from
	unusual shape of location
	swollen underground stems
	maintain the shape of the stem
	reduce water loss
	rigid woody tissue
	in softer turgid tissues

VI. Find synonyms among the pool of words:

Pool of words	Synonyms
1)1.keep/2.replace/3.gain/4.store/5.substitude/6.obtain/
2)1.ground / 2. appear / 3. soil / 4. emerge
3)1.reinforce/2.like/3.situation/4.similar/5.position/6.strengthen
4)1.support / 2. seem / 3. maintain/ 4. appear
5)1.tough/2. strength/3.rigid/4.force/5.locate/6.situate

VII. Answer the following questions. Use all information given before:

1. How is the stem centre called?

2. What kind of form does the vascular tissue take?

3. Where is the tough rigid vascular bundles embedded in?

4. How are vascular bundles arranged in the:

a) dicotyledonous plants

b) monocotyledonous plants?

5. Are the stems of trees supported by parenchyma?

6. What does the epidermis help?

7. What does the inner part of the stems consist of?

8. What is epidermis covered with?

9. Where do most stems point?

VIII. Match the sentence halves. Make complete sentences:

1.	The stems of most plants are foremost organs of support because	A.	upwards from the ground.
2.	Most stems point	B.	parenchyma cells for storage or it may be devoid of cells.
3.	Some stems have an unusual shape of location which	C.	vascular bundles embedded in undifferentiated cells.
4.	All stems of whatever size, shape or location are distinguishable as such by	D.	gaseous exchange takes place.
5.	The epidermis is covered with	E.	they lift terrestrial plants above the ground rising their leaves towards the sun.
6.	Bark is penetrated by small pores called lenticels through which	F.	waxy cuticle to reduce water loss.
7.	The inner parts of the stems of most non-woody plants consist of	G.	makes them more difficult to identify.
8.	Vascular tissue in the stem take the form of	H.	the presence of nods and internodes.
9.	The stem centre is called pitch. It may consist of	I.	bundles containing phloem and xylem and reinforces with strong fibres.

IX. Read and translate the short text without any dictionary:

Fact of life:

The stems of woody plants have a layer of protective tissue called cork, just below the epidermis. Cork is made of dead cells coated with a waxy substance (suberin) which makes them waterproof. The exceptionally thick cork layer of the oak (quercus suber) is removed for commercial use. If cork formed a complete layer, stem cells would die because they wouldn’t be able to exchange respiration gases with the environment. However, slit-like openings called lenticels develop in the cork. The lenticels contain loosely packed thin-walled dead cells which lack suberin, and they have large intercellular spaces to allow gaseous exchange.

X. Food for thought:

Cacti live in hot dry American deserts. To conserve water and deter herbivores, their leaves lose their photosynthesising function and are modified into spines. Nevertheless, cacti may lose as much as 20 per cent of their tissue fluids in a severe drought. Suggest how the stem is adapted to:

a) carry out photosynthesis

b) minimise water losses and minimise the effect on the plant of water-losses.

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