2.88: Understand the Function of the Eye in Focusing Near and Distant Objects, and in Responding to Changes in Light Intensity

NEAR AND DISTANT OBJECTS:

NEAR OBJECT	DISTANT OBJECT
Diagram Showing the Eye when Object is Near	Diagram Showing the Eye when Object is Far
Incoming Light is Divergent Ciliary Muscles will Contract, Suspensory Ligaments will Slack This Allows Lens to Become Fatter, Light is Refracted More Light Converges on Retina	Incoming Light is Parallel Ciliary Muscles Relax, Suspensory Ligaments will Stretch This Allows Lens to Become Thinner, Light is Refracted Less Light Converges on Retina

OBJECT	CILIARY MUSCLES	SUSPENSORY LIGAMENTS	MUSCLE TENSION ON LENS	LENS SHAPE
NEAR	Contracted	Slackened	Low	Fat, More Curved
DISTANT	Relaxed	Stretched	High	Thin, Less Curved

DARK AND BRIGHT ENVIRONMENT:

DARK	BRIGHT
Diagram Showing the Eye in a Dark Environment	Diagram Showing the Eye in a Bright Environment
Photoreceptors Detect Change in Environment (Dark) Reflex Occurs, Muscle in Iris are Effectors: Radial Muscles will Contract, Circular Muscles will Relax Pupil Dilates, Diameter of Pupil Widens and More Light Enters the Eye	Photoreceptors Detect Change in Environment (Bright) Reflex Occurs, Muscle in Iris are Effectors: Radial Muscles will Relax, Circular Muscles will Contract Pupil Constricts, Diameter of Pupil Narrows and Less Light Enters the Eye

ENVIRONMENT	RADIAL MUSCLES	CIRCULAR MUSCLES	PUPIL SIZE	AMOUNT OF LIGHT ENTERS
DARK	Contracted	Relaxed	Wide	More
BRIGHT	Relaxed	Contracted	Narrow	Less