Biologists Are Not Yet Able to Apply the Phylogenetic Species

question 39

Multiple Choice

Biologists are not yet able to apply the phylogenetic species concept to all forms of life because ____.

• A) individuals within populations exhibit genotypic and phenotypic variation
• B) detailed evolutionary histories have been described for relatively few groups of organisms
• C) many forms of life reproduce asexually
• D) evolutionary history cannot be determined for extinct species
• E) it does not distinguish closely related species that are nearly identical in appearance

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Definitions:

Cholecystokinin

A hormone released by the small intestine that stimulates the digestion of fat and protein, and also acts as a satiety signal to the brain.

Fat Cells

Cells that specialize in storing energy as fat, known scientifically as adipocytes, playing a significant role in metabolism and energy balance.

Serotonin

Serotonin is a neurotransmitter that plays a key role in regulating mood, appetite, sleep, memory, and other bodily functions.

Dopamine

A neurotransmitter involved in control of movement, emotion, motivation, and feelings of pleasure.