Text b lungs

Vocabulary list to text b

abdominal (cavity) n	[æbˈdɒmɪnəl]	брюшная полость
cavity n	[ˈkævɪti]	полость
depth n (of breathing)	[depθ]	глубина (дыхания)
diaphragm n	[ˈdaɪəfræm]	диафрагма
due prep	[djuː]	из-за, благодаря
expel v	[ɪkˈspel]	вытеснять, выталкивать
hindbrain n	[ˈhaɪn(d)-breɪn]	задний мозг
increase v	[ɪnˈkriːs]	увеличить
medulla oblongata n	[məˈdʌlə]	продолговатый мозг
pons n	[ˈpɒnz]	варолиев мост
thoracic (cavity) n	[θəˌræsɪk]	грудная полость
unconscious adj	[ʌnˈkɒnʃəs]	бессознательный
ventilate v	[ˈventɪleɪt]	вентилировать

 

The term “respiration” means the exchange of gases (oxygen and carbon dioxide) which takes place between the living organism and the environment. In air-breathing vertebrates respiration takes place in the respiratory organs called lungs. The lungs fill most of the chest or thoracic cavity, which is completely separated from the abdominal cavity by the diaphragm. The lungs are actively ventilated  due to inhalation and exhalation. The passage of air into the lungs to supply the body with oxygen is known as inhalation and the passage of air out of the lungs to expel carbon dioxide is known as exhalation; this process is collectively called breathing or ventilation. When mammals breathe in, the muscle below the rib cage (called the diaphragm) is pulled down, and air gets sucked into the rib cage, filling the lungs. Blood cells circulating through tiny blood vessels near the lungs pick up oxygen and carry it around the body.  Then air is forced out of the lungs as the diaphragm moves up. The air animals breathe in consists of 21% oxygen and 0.04% carbon dioxide. Expelled air consists of 16% oxygen and 4.4% carbon dioxide.  Gas exchange occurs in the pulmonary alveoli by passive diffusion of gases between the alveolar gas and the blood in lung capillaries. Thus, the wastes are removed and the oxygen is taken up by the blood.

Breathing is usually an unconscious activity that takes place whether you are awake or asleep. Two regions in the hindbrain called the medulla oblongata and pons control the rate of breathing. These are called respiratory centers. They respond to the concentration of carbon dioxide in the blood. When this concentration rises during some kind of activity nerve impulses are automatically sent to the diaphragm and rib muscles that increase the rate and the depth of breathing. Increasing the rate of breathing also increases the amount of oxygen in the blood to meet the needs of this increased activity.

Exercise 8. How do movements of the ribs and diaphragm bring about inspiration? Circle the correct statement below. (For the right answer look at the picture below.) a) The diaphragm domes up into the thorax and ribs move in and down. b) The diaphragm flattens and ribs move up and out. c) The diaphragm domes up into the thorax and the ribs move up and out. d) The diaphragm flattens and the ribs move in and down.