IB Bio Topic 6.4

Front

What is ventilation?

Back

The process of breathing that includes inspiration (inhaling) and expiration (exhaling), facilitating gas exchange in the lungs.

Front

What physical movements in the thorax bring fresh air to the alveoli?

Back

Ventilation.

Front

What happens when the diaphragm relaxes?

Back

It creates a decrease in the volume of the chest cavity, leading to expiration.

Front

How does ventilation affect oxygen concentration in the alveoli?

Back

Ventilation maintains a high concentration of oxygen in the alveoli.

Front

What maintains a low concentration of oxygen in blood capillaries near the alveoli?

Back

Circulation.

Front

Why is an oxygen mask used for patients with severe lung disease?

Back

It increases the concentration gradient for oxygen between the alveoli and blood capillaries, enhancing oxygen diffusion.

Front

Define gas exchange.

Back

The process by which oxygen is transferred from the alveoli to the blood and carbon dioxide is removed from the blood to the alveoli.

Front

What is the role of the diaphragm in breathing?

Back

The diaphragm contracts to increase the volume of the chest cavity during inspiration and relaxes to decrease the volume during expiration.

Front

What is the difference between inspiration and expiration?

Back

Inspiration is the intake of air into the lungs, while expiration is the expulsion of air from the lungs.

Front

What is the significance of the concentration gradient in respiration?

Back

A higher concentration of oxygen in the alveoli compared to the blood capillaries facilitates the diffusion of oxygen into the blood.