The Human Respiratory System

Human respiratory system is the system in humans that takes up ....... and expels ......

• oxygen and carbon dioxide

• carbon dioxide and oxygen

• nitrogen and carbon dioxide

• oxygen and nitrogen

2. Flap of tissue that covers the opening to the windpipe during swallowing

• Trachea

• Epiglottis

• Pharynx

• bronchioles

1. The air sacs that are covered with capillaries where gas exchange takes place

• bronchi

• alveoli

• lungs

• oxygen

3. The only externally visible part of the respiratory system

• eyes

• mucus

• Pharynx

• nose

5. The two narrower tubes branching from the trachea that leads into the lungs

• epiglottis

• bronchi

• Pharynx

• alveoli

6. The large muscle that contracts and relaxes and moves air in and out of the lungs.

• soft muscles

• intercostal muscles

• diaphragm

• alveoli

7. An air tube that is held open by C-shaped rings of cartilage. Also known as the windpipe.

• bronchi

• trachea

• lungs

• alveoli

8. The air tubes in your lungs branch off into smaller, narrower tubes called

• bronchi

• trachea

• lungs

• bronchioles

9. Tiny hair like structures that line your nose and most other airways of the respiratory system.

• mucus

• nostril

• cilia

• hair

The air sacs that are covered with capillaries where gas exchange takes place

• bronchi
• lungs
• oxygen
• alveoli