Respiratory System Quiz

Name the structure a to h of the breathing system.

a

b

c

d

e

f

g

h

lung

alveolus

trachea

intercostal muscles

diaphragm

bronchus

rib

bronchiole

Arrange the following structures to show the structures that a molecule of oxygen passes through before entering the blood during inhalation.

• Mouth/Nose

• Bronchiole

• Alveoli

• Bronchus

• Trachea

Arrange the following structures to show the structures that a molecule of oxygen passes through after leaving a red blood cell during exhalation.

• Bronchus

• Bronchiole

• Alveoli

• Trachea

• Mouth/Nose

What is the function of the trachea in the respiratory system?

• To exchange gases with the blood.

• To warm, moisten, and filter air before it reaches the lungs.

• To carry air to and from the lungs.

• To produce mucus to trap pathogens.

Answer explanation

The trachea's primary function is to carry air to and from the lungs, acting as a passageway for airflow. While it also helps filter and moisten air, its main role is transportation.

What is the primary function of the alveoli?

• To pump oxygen into the bloodstream.

• To allow gas exchange between air and blood.

• To filter dust particles from inhaled air.

• To move air in and out of the lungs.

Answer explanation

The primary function of the alveoli is to allow gas exchange between air and blood. They are tiny air sacs in the lungs where oxygen is absorbed into the bloodstream and carbon dioxide is released.

The bronchi branch into smaller tubes called bronchioles. What is their function?

• To support the structure of the trachea.

• To carry air directly to the alveoli.

• To filter oxygen from the air.

• To prevent air from escaping the lungs.

Answer explanation

The bronchioles are responsible for carrying air directly to the alveoli, where gas exchange occurs. This function is crucial for delivering oxygen to the blood and removing carbon dioxide from it.

During inhalation, what happens to the diaphragm?

• It relaxes and moves up.

• It contracts and moves down.

• It contracts and moves up.

• It relaxes and moves down.

Answer explanation

During inhalation, the diaphragm contracts and moves down, increasing the thoracic cavity's volume and allowing air to flow into the lungs. This is why the correct answer is 'It contracts and moves down.'

During inhalation, the volume inside the chest cavity:

• Stays the same.

• Decreases.

• Increases.

• Alternates between increasing and decreasing.

Answer explanation

During inhalation, the diaphragm contracts, increasing the chest cavity's volume. This decrease in pressure allows air to flow into the lungs, making 'increases' the correct answer.

Which of the following helps draw air into the lungs during inhalation?

• Increased chest pressure.

• Decreased chest pressure.

• Relaxation of rib muscles.

Answer explanation

Decreased chest pressure during inhalation allows air to flow into the lungs. As the diaphragm contracts and rib muscles relax, the thoracic cavity expands, lowering pressure and drawing air in.

During exhalation, what happens to the muscles between your ribs?

• They relax, pulling the ribcage down and in.

• They contract, pulling the ribcage up and out.

• They relax, pushing the ribcage up and out.

• They contract, pushing the ribcage down and in.

Answer explanation

During exhalation, the muscles between the ribs, known as intercostal muscles, relax. This relaxation allows the ribcage to move down and in, facilitating the expulsion of air from the lungs.