ЛЕКЦИЯ № 31. Trachea

The trachea, a hollow cylinder supported by 16-20 cartilaginous rings, is continuous with the larynx above and the branching primary bronchi below.

Mucosa of the trachea consists of the typical respiratory epitheli um, an unusually thick basement membrane, and an underlying lamina propria that is rich in elastin. The lamina propria contains loose elastic tissue with blood vessels, lymphatics, and defensive cells. The outer edge of the lamina propria is defined by a dense network of elastic fibers.

Submucosa consists of dense elastic connective tissue with serorilt-fcous glands whose ducts open onto the surface of the epithe lium.

Cartilage rings are C-shaped hyaline cartilage pieces whose free extremities point dorsally (posteriorly). They are covered by a pe-richondrium of fibrous connective tissue that surrounds each of the cartilages. Smooth muscle bundles (trachealis muscle) and ligaments span the dorsal part of each cartilage.

Adventita a consists of peripheral dense connective tissue that binds the trachea to surrounding tissues.

Primary bronchi

The trachea branches at its distal end into the two primary bronchi. Short extrapulmonary segments of the primary bronchi exist before they enter the lungs at the hilus and then branch further. The histologic structure of the walls of the extrapulmonary segment of the primary bronchi is similar to that of the tracheal wall.

New words

hollow – пустота

cylinder – цилиндр

supported – поддержанный

cartilaginous rings – хрящевые кольца

larynx – гортань

above – выше

branching – переход

primary bronchi – первичные бронхи

below – ниже

mucosa – слизистая оболочка

typical – типичный

respiratory epitheli um – дыхательный эпителий

an unusually – нетипитчно

thick – толстый

basement – основание

underlying – основной

lamina – тонкая пластинка

rich – богатый

elastin – эластин

loose – свободный

vessel – сосуд

lymphatics – лимфатический

defensive cells – защитные клетки

outer – внешний

edge – край

Много: MUCH, MANY, (A) LITTLE, (A) FEW

Единственное число: much (используется только исчисляемыми существительными).

Ex. I have much time.

Множественное число: many (используется только с неисчис-ляемыми существительными)

Ex. I have many books.

Переведите на английский язык следующие пары слов.

Много тетрадей, много молока, много воды, много дней, много газет, много мела, много снега, много лет, много картин, много музыки, много мальчиков, много девочек, много чая, много лимонов, много мяса, много комнат, много учителей, много работы, много воздуха, много птиц, много машин.

Вставьте much или many.

1. Please, don't put… peррег on the meat.

2. There were. plates on the table.

3. I never eat. bread with soup.

4. Why did you eat so. ice-cream?

5. She wrote us. letters from the coun try.

6… of these students don't like to look up words in the dictionary.

7.. in this work was too difficult for me.

8… of their answers were excel lent.

9..of their conversation was about the in stitute.

10. There are… new pictures in this room.

Answer the questions.

1. How many cartilaginous rings support the trachea?

2. What is the trachea continuous with?

3. What does mucosa of the trachea consist of?

4. What does the lamina propria contain?

5. With help of what is the outer edges of the lamina propria defined by?

6. What does submucosa consist of?

7. How are cartilage rings shaped?

8. What covers the cartilage rings?

9. What does adventitia consist of?

10. How do short extrapulmanory segments of the primary bronchi exist?

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

Make the sentences of your own using MUCH, MANY, (A) LITTLE,

(A) FEW(10 sentences).

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) vein; b) mucosa; c) trachea;

2) a) mucosa; b) organ; c) submucosa;

3) a) nerve; b) bone; c) organ;

4) a) brain; b) reflex; c) vertebra;

5) a) vision; b) eye; c) ear.