A Swim Bladder Is a Gas-Filled Sac That Helps Fish

question 17

Multiple Choice

A swim bladder is a gas-filled sac that helps fish maintain buoyancy. The evolution of the swim bladder from the air-breathing organ (a simple lung) of an ancestral fish is an example of ________.

• A) exaptation
• B) changes in Hox gene expression
• C) paedomorphosis
• D) adaptive radiation

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Definitions:

Gross Domestic Product

The total value of all goods and services produced within a country's borders in a specific time period, used as a broad indicator of an economy's health.

Income Side

The aspect of national accounts that deals with how income is generated, distributed, and used in an economy, typically measuring aspects like wages, rents, and profits.

Aggregate Income

The total income earned by all individuals and entities in an economy over a specific time period.

Final Output

The total value of goods and services produced by an economy after adjusting for intermediate goods used in production, representing the end products available for consumption, investment, exports, and government spending.