The Earliest Mammals Had a Single Line of Descent into the Monotremes

question 55

True/False

The earliest mammals had a single line of descent into the monotremes, which are the ancestors for all modern mammals.

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Definitions:

Excited By

Stimulated or activated by an external source, leading to an increased level of energy or activity.

Pressure

The force exerted per unit area; in fluids, it is often caused by gravity acting upon the fluid's mass.

Photoreceptors

Specialized cells located in the retina of the eye that are sensitive to light, enabling vision.

Vertebrate Eye

The complex optical organ in vertebrates that enables vision by detecting light and converting it into electro-chemical impulses in neurons.