Which of the Following Are Unique to Mammals and the Most

question 88

Multiple Choice

Which of the following are unique to mammals and the most recent common ancestor of mammals but lacking in nonmammals?

• A) fur and teeth
• B) fur and mammary glands
• C) mammary glands and teeth
• D) teeth and an opposable thumb

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Definitions:

Sodium Channels

A type of ion channel found in the membranes of cells, specifically permeable to sodium ions, crucial for initiating and conducting electrical signals in neurons.

Action Potentials

Rapid and temporary electrical impulses that travel along neurons, essential for nerve impulse transmission.

Axon Hillock

The cone-shaped region of an axon of a neuron where the axon joins the cell body, and where action potentials are initiated.

Initial Segment

The part of a neuron where the axon originates from the cell body, crucial for the initiation of action potentials.