Respiratory System Quiz

What is the primary function of the respiratory system?

• Gas exchange

• Digestion

• Circulation

• Nervous response

What are the major organs of the respiratory system?

• Nose, pharynx, larynx, trachea, bronchi, lungs

• Heart, arteries, veins

• Stomach, intestines, liver

• Kidneys, bladder

What is the role of surfactant in the alveoli?

• Reduces surface tension

• Increases oxygen absorption

• Filters air

• Prevents infection

What is the process of moving air into the lungs called?

• Inspiration

• Expiration

• Ventilation

• Diffusion

What is the composition of air we breathe?

• 78.6% nitrogen, 20.09% oxygen, 0.04% carbon dioxide

• 50% oxygen, 50% nitrogen

• 100% oxygen

• 21% oxygen, 79% nitrogen

What happens during expiration?

Answer explanation

During expiration, the diaphragm and intercostal muscles relax, causing the thoracic cavity to decrease in volume. This increase in pressure forces air out of the lungs, expelling carbon dioxide and allowing fresh air to enter during the next inhalation.

What is the function of the diaphragm during breathing?

Answer explanation

The diaphragm is a dome-shaped muscle that contracts and flattens during inhalation, increasing the thoracic cavity volume and drawing air into the lungs. During exhalation, it relaxes, helping push air out.

Blood coming from the right side of the heart to the lung is low in oxygen. In comparison, the air inspired to the alveolus in the lung is high in oxygen. What happens to the oxygen during gas exchange?

• Oxygen diffuses into the blood of the capillary.

• Oxygen is released into the alveolus.

• Oxygen is converted to carbon dioxide.

• Oxygen remains in the alveolus.

The oxygen-rich blood travels from the lung to the left side of the heart before travelling to the capillaries at the tissues of the body. What is the relationship between the partial pressures of oxygen in the capillaries and the tissues?

• P O2capillary > P O2tissues

• P O2capillary < P O2tissues

• P O2capillary = P O2tissues

• There is no relationship.

What happens to carbon dioxide during gas exchange in the tissues?

• Carbon dioxide diffuses into the blood of the capillary.

• Carbon dioxide is released into the alveolus.

• Carbon dioxide is converted to oxygen.

• Carbon dioxide remains in the tissues.