How Many Substances Are Known or Suspected to Be Neurotransmitters

question 17

Multiple Choice

How many substances are known or suspected to be neurotransmitters?

• A) 8 to 10
• B) thousands
• C) 15 to 20
• D) hundreds

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Definitions:

Life Cycle Assessment (LCA)

A technique used to assess the environmental impacts associated with all the stages of a product's life from raw material extraction through materials processing, manufacture, distribution, use, repair and maintenance, and disposal or recycling.

Cradle to Grave

Considering all stages of a product's life cycle, from raw material extraction (cradle) to disposal or recycling (grave).

Renewable Energy

Energy generated from natural processes that are continuously replenished, such as sunlight, wind, and water flow.

Energy Sources

The origins or types of power, such as fossil fuels, renewable energy, or electricity, used to operate machinery, vehicles, and support human activities.