When Nineteenth Century Scientists Compared Desert Plants, Differences in Their

question 7

Multiple Choice

When nineteenth century scientists compared desert plants, differences in their ____ indicated that these plants could not be as closely related as might otherwise be thought.

• A)​appearance
• B)​spines
• C)​stems
• D)​specific habitats
• E)​reproductive parts

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Definitions:

Refractory Period

A time directly following stimulation in which a nerve or muscle is incapable of responding to more stimulation.

Synapse

The junction or region between the axon of one neuron and the dendrites or cell body of another, through which nerve impulses pass.

Depolarization

A decrease in the difference of electrical charge across a membrane, which can initiate an action potential in neurons.

Neural Membrane

The lipid bi-layer that encloses the cytoplasm of neurons, playing a key role in the transmission of electrical signals within the nervous system.