Eye dilation
The iris is the colored part of the eye. The pupil is the dark circle in the middle of the iris. The iris causes the pupil to expand or contract depending on the amount of light in a given area. Once light passes through the pupil, a structure called the lens that is directly behind the pupil focuses the light at the back of the eye. The optic nerve, located at the back of the eye, takes the focused message and relays it to the brain where it is processed into an image.
Author(s): Greyson Orlando

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Infectivity Groups
Robert G. Whiddon, Ph.D.
Describes infectivity groups as a method to organize the study of microbiology.
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The Upper Limb Anatomy Wiki

Authors: 
Roisin Kelly-Laubscher & students