2.86- The eye

 Describe the structure and function of the eye as a receptor

• The eye is made of three coats: 
• The outermost layer consists of the Cornea and Sclera 
• The middle layer consists of the Cilliary body, Choroid and the Iris 
• The innermost layer consists of the Retina 

• The function of the eye is to receive light and send it to the brain which interprets these signals 
• The light first enters the cornea
• There are no blood vessels in the cornea as the light must be able to travel through uninterrupted 
• The aqueous humour is a nutrient filled liquid which provides nutrients to the cornea and the lens
• The pupil controls how much light passes through from the cornea to the lens
• The iris is two sets of muscle fibres that control the size of the pupil