Упражнение 21

(обзорное)

A. Проанализируйте структуру каждого предложения
и определите его ядро.

Б. Найдите причастие I и определите его функцию в предложении.

B. Переведите предложения.

1. The skin covers the body completely forming a waterproof protective coat that
constitutes the first barrier to invading organisms.

2. The heart is a very powerful muscle, contracting between 60 and 200 times a
minute depending on the level of activity.

3. The diameter of the respiratory passages is altered by contraction or relaxation of
the involuntary muscle in their walls, thus regulating the volume of air entering
the lungs.

4. Arteries supplying contracting muscles dilate, bringing more blood to these organs.

5. Epithelium is layers of cells covering an organ, including the skin and the lining
of all hollow cavities except blood vessels, lymphatics and serous cavities.

6. Endocrine glands may be destroyed by invading tumours, causing hormone
deficiency.

7. Excessive bleeding may deplete the body of circulating blood, causing danger to
the survivor.

8. The smooth muscle layer surrounding blood vessels becomes thicker and stiffer
due to a buildup of calcium and collagen, making the vessels less able to transmit
pressure waves from the heart.

9. More than 100 distinct varieties of cancer are recognized, each having a unique
set of symptoms and requiring a specific course of therapy.

10. Some tumors affecting the pituitary gland result in the secretion of large amounts
of melanocyte-stimulating hormone.

11. Cancer cells penetrate neighboring tissues, destroying normal cells and taking their place.

12. Air containing oxygen and carbon dioxide is breathed into the lungs, filling the
alveoli.

13. Sweat evaporates, thereby removing the heat from the skin and cooling the blood
circulating beneath it.

14. Digitalis strengthens the failing heart, increasing the force of contraction and
producing a more efficient emptying of the ventricles.

15. The human skeleton is composed of 206 bones, with the vertebral column forming
the central supporting structure.

5.3 Причастие II в функции определения