Which of the Following Is an Example of a Commensalism

question 20

Multiple Choice

Which of the following is an example of a commensalism?

• A) fungi residing in plant roots, such as endomycorrhizae
• B) bacteria fixing nitrogen on the roots of some plants
• C) rancher ants that protect aphids in exchange for sugar-rich honeydew
• D) cattle egrets eating insects stirred up by grazing bison

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Definitions:

Serotonin

A neurotransmitter that plays a key role in regulating mood, appetite, and sleep, among other functions, often associated with feelings of well-being and happiness.

Neurotransmitter

A chemical substance that transmits signals across a synapse from one neuron to another.

Glutamate

An important neurotransmitter in the brain involved in learning and memory.

Melatonin

A hormone produced by the pineal gland that regulates sleep and wakefulness.