The video explains the process of breathing and gas exchange in the human body. It describes how oxygen enters through the mouth or nose, travels past the pharynx, larynx, and trachea, and reaches the lungs via the bronchi. In the alveoli, oxygen diffuses into the blood, while carbon dioxide is expelled. The diaphragm and intercostal muscles play a crucial role in facilitating breathing by expanding and contracting the lungs. The video concludes with a recap of these processes.

What is the correct order of structures that air passes through as it enters the body?

• Mouth, Pharynx, Larynx, Trachea

• Nose, Larynx, Pharynx, Trachea

• Pharynx, Mouth, Trachea, Larynx

• Trachea, Larynx, Pharynx, Mouth

Where does the exchange of oxygen and carbon dioxide primarily occur?

• In the trachea

• In the bronchi

• In the alveoli

• In the larynx

What protein in red blood cells binds with oxygen?

• Collagen

• Hemoglobin

• Keratin

• Myoglobin

Which muscle is primarily responsible for helping the lungs expand during breathing?

• Pectoral muscles

• Abdominal muscles

• Diaphragm

• Intercostal muscles

What happens to the diaphragm when you inhale?

• It contracts and moves down

• It relaxes and moves up

• It relaxes and moves down

• It contracts and moves up