respiration

What is the main function of the respiratory system?

• to provide oxygen and remove carbon dioxide from the body

• to break down food and absorb nutrients

• to remove oxygen from the body and deliver carbon dioxide

_________ is the main passageway into and out of the respiratory system.

• mouth

• nose

• ear

• skin pores

The ___________ is the dome（圆顶）shaped muscle below the lungs

• diaphragm

• rib

• alveoli

• trachea

What protects from choking

• pharynx

• epiglottis

• larynx

• trachea

The respiratory system works with the ___________ system to provide our body with oxygen.

• circulatory

• digestive
• muscular
• skeletal

What is oxygen needed for?

• energy releasing chemical reactions

• to make glucose

• to take in sunlight

• none of the above

Why alveoli is so tiny?

• To reduce the surface area for gas exchange
• To make breathing difficult
• To store excess air
• To maximize the surface area for gas exchange

what is found around alveoli?

• capillaries

• pleura

• lymphatic nodes

• saliva

Where does the carbon dioxide in the body originated from?

• Lungs

• Heart

• Atmosphere

• Cell tissues

Which of the following is the correct flow of deoxygenated blood?

• Body tissues -> Heart -> Lungs

• Lungs -> Heart -> Body tissues

• Body tissues -> Lungs -> Heart

• Heart -> Body tissues -> Lungs