The Pupil of the Eye Automatically Constricts When a Bright

question 166

Multiple Choice

The pupil of the eye automatically constricts when a bright light is directed at the eye. What does this illustrate?

• A) a conditioned stimulus
• B) habituation
• C) a conditioned response
• D) an unconditioned response

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Definitions:

Plasma

The liquid component of blood, in which blood cells and other particles are suspended, consisting mostly of water, proteins, and other solutes.

Concentration

The abundance of a constituent divided by the total volume of a mixture.

Osmolality

Osmotic concentration of a solution; the number of moles of solute in 1 kg of water times the number of particles into which the solute dissociates.

Osmoreceptors

Specialized cells in the body that detect changes in plasma osmolality and contribute to the regulation of body fluids.