Using Present Terminology, How Many Bacterial Phyla Have Been Discovered

question 16

Multiple Choice

Using present terminology, how many bacterial phyla have been discovered thus far?

• A) 8, but the actual number may be as high as 25
• B) 4, but the actual number may be as high as 10
• C) 40, but the actual number may be higher
• D) at least 80

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Definitions:

Cognitive Development

The process by which individuals learn and develop mental skills throughout their lives, including thinking, learning, problem-solving, and decision-making.

Ghrelin

A hormone produced by the stomach that stimulates appetite and signals hunger to the brain.

Melatonin

A hormone produced by the pineal gland in the brain, primarily responsible for regulating sleep-wake cycles.

Leptin

A hormone produced by fat cells that helps to regulate energy balance by inhibiting hunger, which in turn diminishes fat storage in adipocytes.