Examine the Evolutionary Tree Pictured Below

question 16

Multiple Choice

Examine the evolutionary tree pictured below.
In this evolutionary tree, which number represents the most recent common ancestor of A, B, and C?

• A) 1
• B) 2
• C) 3
• D) 4

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Definitions:

Load

In physiology, the force or resistance that a muscle has to overcome during contraction; in engineering, the weight or force that a structure supports.

Maximal Stimulus

The level of stimulus at which the maximum rate of contraction or response is achieved in a muscle or nerve.

Treppe Stimulus

A phenomenon where muscle contractions become more forceful with subsequent stimulations, due to increased calcium availability.

Threshold

The minimum level of stimulation required to trigger a neural impulse or a response in a sensory system.