Name the herbs which as they thought in the Middle Ages, combated witchcraft and evil spirits. 


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Name the herbs which as they thought in the Middle Ages, combated witchcraft and evil spirits.



3. Explain the cause of declination of the use of herbs in the 20th century.

 

 

PLANT, ITS PARTS AND THEIR FUNCTIONS

The principal parts of a plant are: 1) the root system, 2) the stems and leaves, 3) the reproductive part made up of flowers, fruits or seeds.

The roots grow downward into the soil and have two main functions— to absorb plant nutrients and water from the soil and to anchor (закріплювати) the plant. As to stems and leaves, they are usually above the ground. The food used in growth by green plants is manufactured in the leaves from the raw materials taken from the soil and air. This process is known as photosynthesis. To support the leaves and to connect them with the roots are the main functions of the stem.

Each flowering plant has leaves. A typical leaf consists of a green, broad, thin portion, the blade (лопатка), which contains a system of vascular tubes called veins. The latter serve as channels for the distribution of water and dissolved substances, and for removing a part of the food which is manufactured in the leaves for the use by the plant.

The shape and the position of the leaves vary to a considerable extent with the species. Leaves may be borne on a leaf stem, or attached directly to the plant. They may be compound as with clovers and potatoes, or simple as in the case of the poplar tree (тополя).

A flower is the part of the plant where seeds are produced. Thus, to produce seeds the plant must have flowers.

A seed consists of an embryo, and one or more seed coats (насіннєва оболонка).

All parts of a plant must be developed well and proportionally enough to function properly. If conditions for plant growth are bad, the plant will be too weak to develop its parts well.

I. Form nouns from the following verbs:

to function, to produce, to develop, lo grow, to know, to cultivate, to use, to describe

II. Make the sentences interrogative:

We can grow plants— Can you grow plants?

1. Man can use plants for food. 2. We must know how a plant grows. 3. All parts of a plant must be developed well to function properly. 4. Leaves may be borne on a leaf stem. 5. To produce seeds the plant must have flowers. 6. We can plant a new variety of corn at our collective farm. 7. The planted trees must be watered.

III. Insert the words from the text into the sentences below:

1. Plants... sources of food... 2. The principal parts of a plant... 3. The roots... into the soil. 4.... is manufactured... 5.... are the main functions of the stem. 6. A typical leaf consists of... 7. A flower is...

IV. Answer the questions:

1. What sources of food are most important for man? 2. Why to your mind is it important to find new uses of plants? 3. What is the reproductive part of the plant made up of? 4. Is the root system as important as stems and leaves? 5. How many functions does the root system of the plant perform? 6. Where is the food necessary for the growth of the plant manufactured? 7. What do leaf veins serve as? 8. How do the shape and the position of leaves vary? 9. What kinds of leaves are distinguished? 10. What are the ways of the leaf attachment?

V. Translate into English:

1. Кисень є необхідним для пророщення насіння.

2. Стовбур цієї рослини має тверду оболонку.

3. Ці рослини добре ростуть в нашому регіоні.

4. Деякі рослини не мають ані листя, ані квітів.

5. Коріння цієї рослини може бути дуже довгим.

HARVESTING AND DRYING

The time of harvesting depends on the purpose for which the herbs are grown. Plants cultivated for their leaves and stems should be harvested in the young stage, before flowering, while herbs grown for their flowers should be picked when in full bloom. Herbs chiefly grown for their seeds are gathered in late summer when the seeds ripen and turn yellow or brown.

Choose a dry, still day for harvesting and gather the herbs after morning dew has vanished, but before the sun becomes hot. Handle the leafy shoots (паростки) carefully to avoid bruising and subsequent loss of aroma, and remove entirely any damaged and discoloured leaves. Large leaves may be stripped from the stems, but small-leaved herbs are better dried whole. If the leaves are gritty (з піском) and dirty, wash them gently in cool water.

If the herbs are wanted for drying, place them on flat containers such as cardboard (картонні) boxes or trays covered with cheesecloth, keeping one kind of herb well apart from another to avoid the mingling (змішування) of aromas. Place the con­tainers in a dry, warm and airy place. An airing cupboard or the warming drawer of a cooker is suitable provided (якщо) there is adequate ventilation.

Turn the herbs once a day, handling them carefully. Most herbs are ready for storing after four or five days or when they are brittle (ламкі) to the touch. Before storing the herbs, check that they are perfectly dry by keeping them in clear glass containers for a week. If moisture (волога) gathers on the inside of the jars, spread out the herbs on trays and leave them to dry for a few more days.

When dry, the leaves should be stripped from the stems, although small-leaved herbs, such as hyssop and thyme, keep their aroma better if stored whole and then crumbled before use. Discard all chaff (відходи) and pack the leaves or sprigs (пагони) into airtight containers. It is best to use opaque (непрозорі, темні) containers; if clear glass jars are used, keep them out of direct light. Seal and label the containers.

Alternatively, small-leaved herbs may be tied in small bunches and hung upside down in a cool airy place to dry. When brittle, strip the leaves from the stems and store in airtight, opaque containers.

Herbs with tender leaves, such as chervil and parsley, are generally unsuitable for drying, but can be preserved by freezing.

Cut the flower spikes of lavender just before they open fully; tie in small bundles and hang upside down in a cool airy place. When completely dry, strip the flowers off the stems and store in airtight containers.

Herbs such as caraway (кмин) and dill (кріп), which are chiefly grown for their seeds, are dried for storage in the same way as leaves. Pick the stems in late summer or early autumn when the seeds are ripe and yellow-brown. Place them on shallow trays, or tie them with their stems in small bunches. Leave to dry for about a week, turning occa­sionally. When dry, remove the seeds and store in the same way as for dried leaves.

Answer the questions to the text:

1. What does the time of harvesting depend on?

2. Should we choose a dry, still day or a rainy one for harvesting?

3. Why should we handle the leafy shoots carefully?

4. What should we do if the leaves are gritty and dirty?

5. How often should we turn the herbs?

6. What herbs are unsuitable for drying?

 

IDENTIFICATION OF HERBS

Identity of entire herbs is determined by their external appearance. In cut and threshed material whole flowers and fruits are chosen and their shape and characteristics are examined using a lens. Leaves, when required, and powders, as a rule, are examined microscopically.

Description. Determined in dry herbs is the colour, odour at trituration (тертя), character of leaf venation and pubescence (пушок) of various parts of the plant. The structure of the fruits is examined with the naked eye, or through a magnifying glass; the length of the stem and the size of flowers or flower heads are measured. After rapid steeping (просочування, занурювання) of the herb in hot water it is flattened out on a glass plate to determine the leaf arrangement.

Powder. Elements of the stem, flowers, seeds and fruits occur in the powder of herbs. Features characteristic of stem parts are larger vessels, fibers and epidermis (peel) cells with straight, lateral walls. As a rule powders contain an insignificant amount of fruit and seed elements.

The material is stored in dry, well-ventilated premises, in a place protected from light; in drugstores — in boxes provided with lids, some hygroscopic herbs — in tins or jars with tight-fitting lids, when necessary — sealed with paraffin.

I. Ttranslate the words with the same root without a dictionary:

Herbage, herbal, herbalist, herbarium, herbivorous, to herborize

II. Name the common structural element of the following nouns:

mixture, moisture, manufacture, fracture, structure, admixture

III. Put question to the italicized words:

I. The structure of the fruits is examined with the naked eye. 2. The material is stored in dry well-ventilated premises, in a place protected from light. 3. Herbs are collected mostly during the period of full flowering. 4. Herbs are not gathered entirely as thick lower stems are often rejected. 5. Similar enzymic activity was found in a variety of plant material. 6. The plant is made up of four principal parts.

IV. Answer the questions:

1. What parts of herbs are examined microscopically? 2. What are stem parts characterized by? 3. What elements do powders contain? 4. What is determined in herbs? 5. Where is the raw material of herbs stored?

 

DRUG EXTRACTION

The principle modes of extraction employed in pharmacy at present are follows: maceration, percolation, digestion, infusion and decoction. Of these percolation is the most important and useful.

Maceration and digestion, which is merely a modified form of maceration, are old processes. The process of maceration consists simply of extraction by soaking the drug or substance in the menstruum (розчинник) until the cellular structure is thoroughly penetrated and the soluble portion softened and dissolved. The usual method is to introduce the drug into a bottle with the solvent, stopper it tightly, and agitate (струшувати) it occasionally for a period ranging from 2 to 14 days, then to pour off the liquid, express (вичавити) the residue to avoid loss, and filter the mixed liquids. The drugs macerated in definite quantities of menstruum, which consists of alcohol of various strengths, ether and alcohol, or other specified solvent.

Percolation, or lixiviation, is the extraction process in which a granulated or powdered drug is deprived of its constituents by the descent of a suitable solvent through it.

The physical forces playing an important part in percolation are gravitation, viscosity, adhesion, friction, osmosis, capillarity, ice tension, and solution.

The instrument used to hold the powder is called a percolator, the liquid poured on top of the powder, the menstruum; the liquid

coming from the percolator, the percolate; and the residual drug remaining in the percolator after the extraction of the soluble constituents, is called the mare.

In order to understand thoroughly the process of percolation as applied to powdered drugs, it must be remembered that the soluble principles of vegetable substances are in hard and dry condition, and are generally contained in cells which are more or less disintegrated by the process of grinding. If the soluble principles could lie separated from the insoluble cellular substance and be deposited in the ground particles, percolation would be rapid.

But the powdering of the drug only partially separated the soluble principles from the insoluble and the finest dust of the powdered always contains a larger proportion of the soluble principles than of the insoluble substance. Hence the first proportion of the percolate is usually the most dense, the most highly coloured, and contains the largest proportion of the soluble principles.

 

SOLUTIONS

Any chemically and physically homogeneous mixture of two or more substances is said to be a solution. It is possible to have solutions of solids in liquids, liquids in liquids, gases in liquids, solids in solids, etc.

Depending upon the size of the dispersed particles we recognize true solutions, colloidal solutions, and suspensions.

If sugar is dissolved in water, it is supposed that the ultimate (кінцева, елементарна) sugar particle is of molecular dimensions (розміри) and that a true solution is formed. On the other hand if very fine sand is mixed with water, a suspension of comparatively large particles, each consisting of many molecules is obtained. Between these two extremes lie colloidal solutions.

From the pharmaceutical stand-point solutions of solids in liquids are of the greatest importance and many quantitative data are available on the properties of such solutions.

When an excess of a solid is brought into contact with a liquid, molecules of the former (першого) are removed from its surface until equilibrium (рівновага) is established between the molecules leaving the solid and those returning to it. The resulting solution is said to be saturated at the temperature of the experiment.

The extent of solubility of different substances varies from almost imperceptible (невідчутний) amounts to relatively large quantities but for any given solute the solubility has a constant value at constant temperature.

Under certain conditions it is possible to prepare a solution containing a larger amount of solute than is necessary to form a saturated solution.

 



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