Английский язык для медиков: конспект лекций

8. The teacher (to understand) that Marina (not to do) her homework.

9. I (to know) that my friend (not yet to come).

10. Tom (to return) from the cinema at five o'clock.

11. Tom (to t return) from the cinema by five o'clock.

12. I (to finish) my homework at seven o'clock.

13. I (to finish) my homework by seven o'clock.

14. He (to think) that he (to lose) the money.

15. Ann (to tell) me that she (to see) an interesting film.

16. When I (to wake) up yesterday, father already (to go) to work.

17. Nick (to think) that his father (not yet to come) home.

18. Mary (to tell) us that she (to cook) a good dinner.

19. Yesterday I (to find) the book which I (to lose) in summer.

20. When we (to come) to the station, the train already (to leave).

Answer the questions.

1. Which organs are primarily engaged in the intermediary metabolism?

2. Which of 3 organs perform the most diverse functions?

3. How does it act?

4. Which role does liver play?

5. What does it control?

6. Where the cholesterol esters are concentrated?

7. What the bile is necessary for?

8. What does liver utilize?

9. What prevents the clotting of the blood?

10. What is the most important gland of the body?

Make the sentences of your own using the new words (10 sentences).

Find the Present Simple Tense in the text. Explain why it is used in such a way?

Find one word, which is a little bit different in meaning from others (найдите одно слово, которое немного отличается от других по смыслу):

1) a) liver; b) jam; c) kidney;

2) a) pancreas; b)organ; c) winter;

3) a) summer; b) blood; c) vein;

4) a) cholesterol; b) ice; c) bile;

5) a) clotting; b) snow; c) vessel.

ЛЕКЦИЯ № 43. The urinary system

The urinary system, consisting of the kidneys, bladder, and excretory ducts (ureters and urethra) is formed mainly from mesodermal and endodermal derivatives with a smaller con tribution from the ectoderm. Three separate systems form sequentially. The pronephros is vestigial; the mesonephros may function transiently, but then mainly disappears; the metanephros develops into the definitive kidney. The pronephric/ mesonephric ducts provide important contribu tions to the male reproductive system. The permanent excre tory ducts are derived from the metanephric ducts, the uro-genital sinus, and surface ectoderm.

Renal development is characterized by three successive, slightly over lapping kidney systems.

Pronephros: Segmented nephrotomes appear in the cervical intermediate mesoderm of the embryo in the fourth week. These structures grow laterally and canalize to form nephric tubules. Successive tubules grow caudally and unite to form the pronephric duct, which empties into the cloaca. The first tubules formed regress before the last ones are formed. By the end of the fourth week, the pronephros disappears.

Mesonephros: In the fifth week, the mesonephros appears as «S-shaped» tubules in the intermediate mesoderm of the thoracic and lumbar regions of the embryo.

The medial end of each tubule enlarges to form a Bowman's capsule into which a tuft of capillaries, or glomerulus, invaginates.

The lateral end of each tubule opens into the mesonephriс (Wolffi-an) duct, an intermediate mesoderm derivative.

Mesonephric tubules function temporarily and degenerate by the beginning of the third month. The mesonephric duct pesists in the male as the ductus epididymidis, ductus deferens, and the ejaculatory duct.

Metanephros: During the fifth week, the metanephros, or permanent kidney, develops from two sources: the ureteric bud, a diverti-culum of the mesonephric duct, and the metanephric mas, from intermediate mesoderrn of the lumbar and sacral regions. The ureteric bud penetrates the metanephric mass, which cordenses around the diverti-culum to form the metanephrogen cap. The bud dilates to form the renal pelvis, which subsequently splits into the cranial and caudal major calyces. Each major calyx buds into the metanephric tissue to form the minor calyces. One-to-three million collecting tubules develop from the minor calyces, thus forming the renal pyramids. Penetration of collecting tubules into the metanephric mass induces cells of the tissue cap to form nephrons, or excretory units. The proximal nephron forms Bowman's capsule, wherea the distal nephron connects to a collecting tubule.

Lengtheningy of the excretory tubule gives rise to the proximal convoluted tubule, loop of Henle, and the distal convoluted tubule.

The kidneys develop in the pelvis but appear to «ascend» into the abdomen as a result of fetal growth of the lumbar and sacral regions. With their ascent, the ureters elongate, and the kidneys become vascu-larized by lateral splanchnic arteries, which arise from the abdominal aorta.

Bladder and urethra