An Increase in Altitude Reduces the O₂ Supply for Air

question 58

Multiple Choice

An increase in altitude reduces the O₂ supply for air breathers because at higher altitudes,

• A) oxygen makes up a smaller percentage of the gases in air.
• B) atmospheric pressure decreases.
• C) temperature of air decreases.
• D) humidity increases.
• E) increased fluid coats the respiratory membranes.

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Definitions:

Synapomorphies

Shared derived characteristics or traits that are used to group organisms together, indicating common ancestry.

Dolphins

Intelligent aquatic mammals known for their complex behaviors and communication skills, belonging to the family Delphinidae.

Mammals

Warm-blooded vertebrates characterized by the presence of mammary glands which produce milk for feeding their young, and typically possessing hair or fur.

Monophyletic

A group of organisms that consists of all the descendants of a common ancestor.