B. Leukocytes

Leukocytes, or white blood cells, are not so numerous as erythrocytes. The researchers have not yet understood their physiology completely. They have studied well the functions of leukocytes in disease, but not in health. The scientists have made numerous studies of their cytology.

Biologists have divided leukocytes into three main groups: lymphocytes, monocytes, and granulocytes. The granulocytes are characterized by specific granules in their cytoplasm, and the scientists have classed them as neutrophils, eosinophils and basophils according to their staining reactions (staining reactions — особенности окрашивания). Recent opinion is that all leukocytes exert their main functions, not in the blood stream, but in the tissues. The blood is a means of transport of leukocytes.

Упражнение 1. Переведите на русский следующие словосочетания:

1) recent opinion 2) staining reactions 3) classed according to staining reactions 4) blood stream

Упражнение 2. Ответьте на следующие вопросы:

1. Into how many groups have the biologists divided leukocytes?

2. What are granulocytes characterized by?

3. How have the scientists classed the granulocytes?

4. Where do the leukocytes exert their function?

Упражнение 3.Перескажите текст B. При пересказе употребите глаголы в форме Present Perfect.

Упражнение 4. Раскройте скобки. Поставьте глаголы, данные в скобках, в одно из времен группы Perfect. Переведите предложения на русский язык:

1) The assistant (to disinfect) the instruments before the operation began.

2) We (to make) numerous experiments before we published new data about main functions of leukocytes.

3) Scientists (to find) that structurally the cells of epithelial tissues are flat, cubical, columnar, or ciliated.

4) We (to publish) the article by May.

Упражнение 5. Переведите предложения на английский язык. Употребите сказуемое в форме Present Perfect.

1) Ученые разделили лейкоциты на 3 группы: лимфоциты, моноциты и гранулоциты.

2) Ученые провели многочисленные исследования в области морфологии лейкоцитов.

3) В недавние годы ученые опубликовали новые сведения о функциях лейкоцитов.

Задание 56. Выучите лексику темы “ Classification of Tissues”.

Задание 57. Перескажите текст A.