Today, __________ of the World's Population Lives in Cities

question 21

Multiple Choice

Today, __________ of the world's population lives in cities.

• A) less than half
• B) 65 percent
• C) 75 percent
• D) almost 90 percent

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Definitions:

Ion Channel-linked Receptor

A type of cell surface receptor that opens or closes a channel across the cell membrane in response to the binding of a signaling molecule, allowing specific ions to pass through.

G Protein-linked Receptor

A type of cell surface receptor that activates G proteins in response to the binding of a signaling molecule, playing a pivotal role in various signal transduction pathways.

GDP

Gross Domestic Product, a measure of the economic performance of a country, representing the total value of all goods and services produced over a specific time period.

GTP

Guanosine triphosphate, a molecule that provides energy for various cellular processes similar to ATP.