Gas Exchange Grade 7 IGCSE

What is the structure and function of alveoli in gas exchange?

• Alveoli absorb gases from the bloodstream

• Alveoli store excess oxygen in the lungs

• Alveoli release carbon dioxide into the bloodstream

• Alveoli facilitate the exchange of oxygen and carbon dioxide between the lungs and the bloodstream.

Explain the process of diffusion of gases in the context of gas exchange.

• Diffusion occurs through active transport

• The process involves the release of energy

• Gases move from low to high concentration

• Gases move from high to low concentration across a semipermeable membrane.

How does gas exchange take place in the respiratory system?

• Gas exchange occurs through the skin instead of the respiratory system.

• The respiratory system absorbs gases through the digestive tract.

• Carbon dioxide diffuses into the bloodstream, and oxygen diffuses into the air in the alveoli.

• Oxygen diffuses into the bloodstream, and carbon dioxide diffuses into the air in the alveoli.

What are air sacs and their role in gas exchange?

• Air sacs are responsible for regulating body temperature.

• Air sacs are found in the brain and control breathing.

• Air sacs are structures in the lungs where gas exchange occurs, allowing oxygen to enter the bloodstream and carbon dioxide to exit the body.

• Air sacs are located in the stomach and aid in digestion.

Why is the structure of alveoli important for efficient gas exchange?

• The structure of alveoli is rigid and inflexible, hindering gas exchange

• Alveoli have a thick membrane that slows down gas exchange

• Alveoli lack blood vessels, limiting gas exchange efficiency

• The structure of alveoli provides a large surface area, thin walls, and a dense capillary network for efficient gas exchange.

Explain how oxygen and carbon dioxide are exchanged in the alveoli.

• Carbon dioxide diffuses into the bloodstream, and oxygen diffuses out of the bloodstream in the alveoli.

• Oxygen is exhaled from the alveoli, and carbon dioxide is inhaled into the bloodstream.

• Oxygen is converted into carbon dioxide in the alveoli.

• Oxygen diffuses into the bloodstream, and carbon dioxide diffuses out of the bloodstream in the alveoli.

Discuss the role of capillaries in the exchange of gases at the alveoli.

• Capillaries regulate blood pressure in the alveoli

• Capillaries store excess gases in the alveoli

• Capillaries facilitate the exchange of oxygen and carbon dioxide between the alveoli and the bloodstream.

• Capillaries transport nutrients to the alveoli

How does the surface area of alveoli impact the efficiency of gas exchange?

• The surface area of alveoli does not impact the efficiency of gas exchange.

• The smaller the surface area of alveoli, the more efficient the gas exchange process.

• Alveoli with irregular surface area are more efficient in gas exchange.

• The larger the surface area of alveoli, the more efficient the gas exchange process.