The structure of the human eye that adjusts the amount of light entering it is the
Correct answer: B. iris
- A. retina
- B. iris
- C. lens
- D. cornea
Explanation
Muscles of the iris widen or narrow the pupil, letting more light in during darkness and less in bright sun. The lens focuses light and the cornea refracts it, but neither controls the quantity of light entering the eye.
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About Receptors
Receptors are specialized cells or proteins that detect stimuli such as light, sound, pressure, temperature and chemicals, then initiate responses through sensory or hormonal pathways. Questions distinguish sensory receptors from effectors, compare receptor types, and examine stimulus conversion into nerve impulses, including the roles of rods, cones, chemoreceptors and mechanoreceptors.
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