Autotrophs Are Useful Because

question 40

Multiple Choice

Autotrophs are useful because

• A) they remove carbon dioxide from the air.
• B) they add oxygen to the air.
• C) they are a source of food for humans.
• D) some are a potential source of fuel.
• E) All of the above.

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Definitions:

Excitation

The process of stimulating activity in an organism or in any of its parts, often leading to increased activity or responsiveness.

Synapses

The junctions between neurons through which they communicate with each other using chemical or electrical signals.

Presynaptic Neuron

The neuron that sends a signal across the synapse to another neuron.

Neurotransmitter

Chemical substances released by neurons to transmit signals across a synapse to another neuron or to a muscle or gland cell.