To State That a Particular Teratogen Has an Effect During

question 40

Multiple Choice

To state that a particular teratogen has an effect during a "critical period" means that it:

• A) can affect organ systems that are critical for sustaining life
• B) can cause the mother to become critically ill and perhaps die
• C) exerts its effect on development only during a particular stage of development
• D) will require the mother to be hospitalized, most likely in a critical care unit

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Definitions:

Myelin Layers

Myelin layers are protective coverings made of fatty substances that surround the axons of some neurons, facilitating the rapid transmission of electrical impulses along nerve cells.

Propagation Speed

The rate at which a wave, including sound, light, or electromagnetic waves, travels through a medium.

Action Potential

A brief change in the electrical charge of a neuronal membrane; the physical basis of the signal that travels the length of the neuron.

Excitation Threshold

The voltage difference between a neuron’s interior and exterior that, if exceeded, causes the neuron to fire.