12R Lung Structure & Ventilation

Which is the correct order of structures through which air travels to get to the alveoli?

• Bronchiole - Trachea - Bronchus - Alveolus

• Trachea - Bronchus - Bronchiole - Alveolus

• Trachea - Bronchiole - Bronchus - Alveolus

• Bronchus - Trachea - Bronchiole - Alveolus

What are the names of structures 1, 2 and 5? (Write your answer in this format: "Structure 1, Structure 2, Structure 5")

This flow chart shows the steps in inspiration. What is happening in steps 2 and 4?

• 2: External intercostals muscles relax, ribs lower

  4: Pressure inside thoracic cavity is reduced

• 2: Internal intercostal muscles contract, ribs raise

  4: Pressure inside the thoracic cavity is reduced

• 2: Internal intercostal muscles contract, ribs lower

  4: Pressure inside the thoracic cavity is increased

• 2: External intercostal muscles contract, ribs raise

  4: Pressure inside the thoracic cavity is reduced

This flow chart shows the stages in expiration. What is happening at stages 1 and 3?

• 1: Diaphragm contracts and moves upwards

  3: Volume inside the chest decreases

• 1: Diaphragm relaxes and moves upwards

  3: Volume inside the chest increases

• 1: Diaphragm relaxes and moves upwards

  3: Volume inside the chest decreases

• 1: Diaphragm relaxes and flattens

  3: Volume inside the chest decreases

Which of the following is not an adaptation of alveoli?

• Moist lining

• Rings of chitin

• Thin walls

• Good blood supply

Why does the alveoli having thin walls increase the efficiency of gas exchange?

• More oxygen can diffuse into the blood

• Diffusion distance is lower so diffusion happens more quickly

• Walls of the alveoli are more permeable

• Thin walls increase the surface area

What two features of their respective gas exchange surfaces are not shared by mammals, insects and fish?

• Specific mechanism to moisten surface

• High surface area

• Good blood supply

• Specific mechanism to maintain a steep concentration gradient

In what structures within the lungs would we see ciliated epithelium?

• Trachea

• Bronchi

• Small Bronchioles

• Alveoli

• Large Bronchioles