The Respiratory System of Birds Is One of the Most

question 23

Multiple Choice

The respiratory system of birds is one of the most effective respiratory systems of all air-breathing organisms, due to its system of air sacs connected to the lungs. Which of the following can be inferred about the air sacs given the observation that they are neither thin nor highly vascularized?

• A) They must not belong to the respiratory system.
• B) They cannot be derived from endoderm.
• C) They are not efficient sites of gas exchange between air and blood.
• D) They cannot effectively moisturize the air before it reaches the lungs.

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Definitions:

Elastic Demand

A situation where the quantity demanded of a good or service changes significantly as its price changes.

Price Elasticity of Demand

An index showing the extent to which demand for a product changes in reaction to a variation in its price, where an elasticity exceeding one signifies a strong response.

Determinants

Factors or elements that contribute to producing a particular result or outcome.

Rebate Program

A promotional offer that refunds part of the purchase price of a product to the customer, usually after submitting a claim form with a receipt.