Respiratory system

Question 1

Describe gas exchange occurring in the lungs

Answer 1

Involves diffusion of O2 inhaled from high conc. in alveoli to a low conc. in bloodstream.

CO2 diffuses from high conc. in bloodstream to low conc in alveoli, where it is exhaled from the lungs.

Question 2

Main function of respiratory system

Answer 2

Provide gas exchange between blood and external environment

Question 3

Function of pharynx

Answer 3

• Provide passageway for food and air
• warm, moisten and protect from infection (mucous membrane)

Question 4

Function of larynx

Answer 4

• Allow air to pass to trachea whilst stopping food and liquids from entering respiratory tract.
• House vocal chords to manipulate pitch and sound.

Question 5

Function of trachea

Answer 5

Provide pathway for air between larynx and bronchus.

Question 6

Function of bronchus/bronchi

Answer 6

Provide pathway between trachea and bronchioles

Question 7

Function of bronchioles

Answer 7

Provide pathway for air between bronchus and alveoli.

Question 8

Function of alveoli

Answer 8

exchange O2 and CO2 to and from bloodstream (gaseous exchange/pulmonary diffusion)

Question 9

Function of pleura

Answer 9

Provide lubrication - reduce friction during movement of lungs during breathing

Question 10

Ventilation

Answer 10

movement of air into and out of lungs via inspiration and exhalation

Question 11

Respiration

Answer 11

Movement of O2 from the external environment to the cells of the body

Question 12

Gaseous exchange

Answer 12

movement of O2 from lungs to bloodstream and elimination of CO2 from bloodstream to lungs down conc. gradient

Question 13

Describe 2 structural features of the alveoli that allow for efficient gas exchange

Answer 13

1 cell thick = increased efficiency for diffusion bc decreased diffusion pathway

Extensive capillary network - increased SA:V ratio t/f increased space for diffusion to occur.

Question 14

Process of inspiration

Answer 14

Diaphragm + intercostal muscles contract move up and out. This leads to increased thoracic volume and decreased intrapulmonary/intrathoracic pressure as air is sucked into lungs.

Question 15

Process of exhalation

Answer 15

Diaphragm and intercostal muscles relax and move down and in. This leads to decreased thoracic volume and increased intrathoracic/intrapulmonary pressure as air is expelled from the lungs.

Question 16

Emphysema

Answer 16

Lung disorder = air becomes trapped in alveoli and bronchioles = difficulty breathing

Question 17

pneumonia

Answer 17

lung inflammation caused by bacterial or viral infection, in which the air sacs fill with pus