All AP Biology Resources
Example Questions
Example Question #4 : Understanding Respiratory Functions
What happens to the pressure of the lungs to initiate inspiration?
Pressure decreases, then increases
Pressure increases
Pressure remains constant
Pressure increases, then decreases
Pressure decreases
Pressure decreases
During inspiration, the lungs expand as the diaphragm contracts and internal intercostal muscles relax. As the volume of the thoracic cavity increases, its pressure decreases. This creates a pressure gradient, driving air from an area of high pressure (the environment) into the area of low pressure (the lungs).
Example Question #4 : Respiratory Physiology
What phenomenon occurs in the blood when an individual holds their breath for an extended period?
Alkalosis
Acidosis
Decreased heart rate
Combustion
Auto-immune disease
Acidosis
When you are not breathing, your respiratory system cannot perform its function. Unwanted gases, such as carbon dioxide, cannot be removed from the system and necessary gases, such as oxygen, cannot enter the system. This causes a buildup of carbon dioxide in the body, which leads to acidosis. Carbon dioxide is converted to carbonic acid via carbonic anhydrase. This carbonic acid builds in the blood, lowering its pH.
Example Question #1 : Understanding Other Respiratory Physiology
Which of the following answers lists the correct order of respiratory structures that air moves through as it is drawn into the lungs?
Alveoli, trachea, bronchi, bronchioles
Bronchi, bronchioles, alveoli, trachea
Trachea, bronchioles, bronchi, alveoli
Trachea, bronchi, bronchioles, alveoli
Trachea, bronchi, bronchioles, alveoli
Air enters the body of most terrestrial vertebrates through the nose or the mouth; the air then passes through the trachea to narrower tubes called the bronchi, to still narrower tubes called the bronchioles. The bronchioles "dead end" into structures called alveoli, which is where gas exchange of oxygen and carbon dioxide takes place with the blood in adjacent capillaries.
Example Question #2 : Understanding Other Respiratory Physiology
Which of the following structures is not found within the lungs?
Trachea
Bronchi
Bronchioles
Alveoli
Trachea
The lungs contain the bronchioles, the alveoli, and part of the bronchi. The trachea carries inhaled air into the bronchi, but it is not actually enclosed by the bronchi— the lungs only enclose structures that arise after the bronchi branch away from the trachea.
Example Question #2 : Understanding Other Respiratory Physiology
Terrestrial animals must combat the drying out of respiratory surfaces due to evaporation. What is one strategy they use?
Increased perspiration of cells on respiratory surface
Increased metabolism
Having very low respiratory rates
Excretion of fluids from walls of lungs
Folding the respiratory surface into the body
Folding the respiratory surface into the body
By folding the respiratory surface into the body, terrestrial animals increase the humidity of the environment of the respiratory surface, which will minimize evaporation and maintain moisture. Note that water loss via evaporation and perspiration accounts for the majority of water loss in terrestrial mammals.