Exchange of Gases

The video explains the process of diffusion, where molecules move from high to low concentration. It covers gaseous exchange at the alveoli and tissue levels, known as external and internal respiration. Factors affecting diffusion include partial pressure, membrane structure, solubility, and surface area. The video details how oxygen and carbon dioxide are exchanged in the lungs and tissues, emphasizing the role of partial pressure gradients.

What is the process called when oxygen enters the pulmonary capillaries from the alveoli?

• Internal respiration

• Cellular respiration

• Pulmonary respiration

• Photosynthesis

Which factor is crucial in determining the direction of gas exchange?

• Humidity

• Wind speed

• Partial pressure

• Temperature

What is the diffusion membrane in the lungs primarily composed of?

• Muscle tissue

• Cartilage

• Three layers including squamous epithelium

• Bone

Why does carbon dioxide diffuse more readily than oxygen across the diffusion membrane?

• It is more soluble in water

• It is more reactive

• It is less dense

• It is lighter

Approximately how many alveoli are present in human lungs?

• 300 million

• 200 million

• 100 million

• 400 million

What is the partial pressure of oxygen in alveolar air after inspiration?

• 120 mm Hg

• 40 mm Hg

• 95 mm Hg

• 105 mm Hg

How does carbon dioxide move from the pulmonary capillaries to the alveoli?

• Through active transport

• Via facilitated diffusion

• By osmosis

• Due to a partial pressure gradient