Human Respiratory System Quiz

What is the main function of the respiratory system?

• To digest food

• To pump blood

• To help us breathe

• To protect the body

Answer explanation

The respiratory system's primary role is to facilitate breathing, which involves taking in oxygen and expelling carbon dioxide, a waste product of cellular respiration.

Which organ is primarily responsible for breathing?

• Heart

• Liver

• Lungs

• Stomach

Answer explanation

The lungs are the main organs of the respiratory system where gas exchange occurs. They are responsible for taking in oxygen from the air and expelling carbon dioxide from the blood.

What tube carries air from the nose to the lungs?

• Esophagus

• Trachea

• Intestine

• Vein

Answer explanation

The trachea, or windpipe, is the tube that connects the throat (pharynx) with the lungs, allowing air to travel to and from the lungs.

Where does the exchange of oxygen and carbon dioxide take place in the lungs?

• Bronchi

• Alveoli

• Diaphragm

• Bronchioles

Which muscle helps the lungs to inhale and exhale air?

• Biceps

• Diaphragm

• Pectoral

• Gluteus

Answer explanation

The diaphragm is the primary muscle involved in breathing. When it contracts, it moves downward, increasing the thoracic cavity's volume and allowing air to flow into the lungs. When it relaxes, it moves upward, helping to expel air from the lungs.

What happens when we inhale?

• Our lungs deflate

• Our diaphragm moves up

• Air goes into our lungs

• We close our eyes

What gas do we breathe in that is necessary for life?

• Oxygen

• b) Carbon dioxide

• Nitrogen

• Helium

What is the process of breathing out called?

• Inhalation

• Circulation

• Exhalation

• Absorption

Which part of the respiratory system filters dust and other particles from the air we breathe in?

• Mouth

• Lungs

• Nose

• Stomach

What gas do we breathe out that our body produces as a waste product?

• Oxygen

• Carbon dioxide

• Nitrogen

• Helium