ventilation

Question 1

what is ventilation?

Answer 1

the process of moving air into and out of the lungs (inhalation and exhalation)

Question 2

what does moving air rely on?

Answer 2

differences in air pressure between the lungs and the atmosphere

Question 3

what is inhalation?

Answer 3

• diaphragm contracts, moving down and flattening
• intercostal muscles contract, moving rib cage up and out
• causes the volume of the thorax to increase and air pressure in the thorax to fall
• air pressure in the thorax is now less than atmospheric pressure, causing air to move into the lungs

Question 4

what is exhalation?

Answer 4

• diaphragm relaxes, moving up and doming
• intercostal muscles relax, moving ribcage down and in
• causes the volume of the thorax to decrease and air pressure in the thorax to rise
• air pressure in the thorax is now more than atmospheric pressure, causing air to move out of the lungs

Question 5

in inhalation what happens to the diaphragm?

Answer 5

diaphragm contracts, moving down and flattening

Question 6

in exhalation what happens to the diaphragm?

Answer 6

diaphragm relaxes, moving up and doming

Question 7

in inhalation what happens to the intercostal muscles?

Answer 7

they contract- moving rib cage up and out

Question 8

in exhalation what happens to the intercostal muscles?

Answer 8

they relax- moving rib cage down and in

Question 9

in inhalation what happens to the volume of the thorax and the air pressure?

Answer 9

• volume of the thorax increases
• air pressure falls

Question 10

in exhalation what happens to the volume of the thorax and the air pressure?

Answer 10

• volume of the thorax decreases
• air pressure rises

Question 11

in inhalation does air move in or out of the lungs?

Answer 11

moves in because air pressure in the thorax is now less than atmospheric pressure

Question 12

in exhalation does air move in or out of the lungs?

Answer 12

moves out because air pressure in the thorax is now more than atmospheric pressure