The Eye LO: To know the structure and function of parts of the eye and how the lens allows us to focus on objects

Optical Illusions:

The Eye Look at the diagram showing the main parts of the eye

Label the eye below:

Parts of the eye: PartFunction Ciliary Muscles Cornea Lens Iris Pupil Retina Suspensory Ligaments

Focussing and Range of Vision How does your focus change if you look up from a book and look out of the window at a distant object? The thickness of the lens is controlled by the ciliary muscles. When you focus on a near object they contract, squeezing the lens and making it thicker. When you change your focus to a far object the ciliary muscles relax and the lens becomes thinner.

What is the range of vision of a normal human eye? 25cm to infinity Near point: 25cm Far point: Infinity This means we can see clearly any object that is within these distances.

How the lens works:

Summary 1a) The front of the pupil is protected by the …. b) The pupil if the eye is at the centre of the ….. c) The ….. of the eye foccuses light onto the …… 2) A person with normal eyesight looks up from a book and observes a distant object. Describe what happens to the shape of the lens.