the human eyes and ears 2.pdf

THE HUMAN EYES AND EARS Parts of the Eyes  CORNE The corneaA is a clear, curved cover at the front of your eye. It helps you see clearly by letting light into your eye and making sure you can focus on things. IRIS The iris is the colored part of the eye that surrounds th...

THE HUMAN EYES AND EARS Parts of the Eyes  CORNE The corneaA is a clear, curved cover at the front of your eye. It helps you see clearly by letting light into your eye and making sure you can focus on things. IRIS The iris is the colored part of the eye that surrounds the pupil. It regulates the amount of light that enters the eye PUPIL The pupil is the hole in the middle of the colored part of your eye. The colored part, called the iris, changes the size of the pupil to let in just the right amount of light LEN S The lens is a clear part of the eye behind the iris that helps to focus light and images on the retina. RETIN A retina is the light-sensitive The tissue at the back of the eye. The retina converts light into electrical impulses that are sent to the brain through the optic nerve.  OPTIC NERVE The optic nerve is the largest sensory nerve of the eye. It carries impulses for sight from the retina to the brain.  QUIZ TIME! What is the clear outer part of the eye’s focusing system called? a) Iris b) Retina c) Cornea d) Lens  QUIZ TIME! What is the colored part of the eye that surrounds the pupil? a) Lens b) Pupil c) Iris d) Retinal  QUIZ TIME! Which part of the eye helps to focus light and images on the retina? a) Cornea b) Iris c) Lens d) Optic nerve  QUIZ TIME! What is the function of the optic nerve? a) To control the size of the pupil b) To carry impulses for sight from the retina to the brain c) To protect the eye from dust d) To adjust the focus of the lens  QUIZ TIME! What is the opening at the center of the iris called? a) Retina b) Pupil c) Cornea d) Lens  TRUE OR FALSE 1) The cornea is the clear, outer part of the eye located at the back of the eye. 2) The iris is responsible for regulating the amount of light that enters the eye. 3) The lens of the eye is located in front of the iris.  TRUE OR FALSE 4) The optic nerve carries visual impulses from the retina to the brain. 5) The pupil is the colored part of the eye that surrounds the iris. Parts of the Ears eardrum OUTER EAR - the visible portion of the ear. The PINNA is made of cartilage covered by skin. It funnels sound into the ear canal. OUTER EAR - the visible portion of the ear. The EAR CANAL is a short tube that transmits sound from the pinna to the eardrum. MIDDLE EAR - vibrations from the eardrum set the ossicles into motion. The EARDRUM is a thin, tough layer of tissue at the end of the auditory canal. Sound waves make the eardrum vibrate MIDDLE EAR - vibrations from the eardrum set the ossicles into motion. OSSICLES, or ear bones, are three tiny bones (HAMMER, ANVIL, AND STIRRUPS) that amplify and transmit the vibrations from the eardrum to the cochlea. INNER EAR - a small compartment which contains the hearing and balance apparatus The COCHLEA is an organ filled with fluid. Receptor cells change vibrations in the fluid into electrical impulses WHO AM I? _____ _______ WHO AM I? ________ _______ WHAT ARE THE THREE SMALLES BONES IN ATHE HUMAN BODY THAT CAN BE SEEN INSIDE THE HUMAN EARS? H____R ST_____S A _V_ _ WHAT ARE THE COMMON EAR PROBLEMS?