There are five general categories of sensory receptors: pain receptors thermoreceptors mechanoreceptors chemoreceptors photoreceptors

Transcription

1 There are five general categories of sensory receptors: pain receptors thermoreceptors mechanoreceptors chemoreceptors photoreceptors 1 of 49

2 Vision The retina is the inner layer of eye that contains photoreceptors. Retina 2 of 49

3 Vision The choroid is the middle layer of eye that is rich in blood vessels. Choroid 3 of 49

4 Vision The sclera is the outer layer of eye that maintains its shape. The sclera serves as point of attachment for muscles that move the eye. Sclera 4 of 49

5 Vision Light enters the eye through the cornea, a tough transparent layer of cells. Cornea 5 of 49

6 Vision The cornea helps focus light, which then passes through a chamber filled with a fluid called aqueous humor. Aqueous humor Cornea 6 of 49

7 Vision At the back of the chamber is a disklike structure called the iris, which is the colored part of the eye. Iris 7 of 49

8 Vision In the middle of the iris is a small opening called the pupil. Muscles in the iris adjust pupil size to regulate the amount of light that enters the eye. Pupil 8 of 49

9 Vision Just behind the iris is the lens. Muscles attached to the lens change its shape to adjust focus to see near or distant objects. Lens 9 of 49

10 Vision Behind the lens is a large chamber filled with a transparent, jellylike fluid called vitreous humor. Vitreous humor 10 of 49

11 Vision The lens focuses light onto the retina. Photoreceptors are arranged in a layer in the retina. Retina 11 of 49

12 Vision Rods are sensitive to light, but not color. Cones respond to light of different colors, producing color vision. 12 of 49

13 Vision Cones are concentrated in the fovea, which is the site of sharpest vision. Fovea 13 of 49

14 Vision The impulses leave each eye by way of the optic nerve. Optic nerves carry impulses to the brain. The brain interprets them as visual images and provides information about the external world. Optic nerve 14 of 49

15 Hearing and Balance The Ear The human ear has two sensory functions: hearing balance 15 of 49

16 Hearing and Balance The Human Ear 16 of 49

17 Hearing and Balance Vibrations enter the ear through the auditory canal. Auditory canal 17 of 49

18 Hearing and Balance The vibrations cause the tympanum, or eardrum, to vibrate. Tympanum 18 of 49

19 Hearing and Balance The vibrations are picked up by the hammer, anvil, and stirrup. Hammer Stirrup Anvil 19 of 49

20 Hearing and Balance The stirrup transmits the vibrations to the oval window. Stirrup Oval window 20 of 49

21 Hearing and Balance Vibrations of the oval window create pressure waves in the fluid-filled cochlea of the inner ear. Cochlea 21 of 49

22 Hearing and Balance Within the inner ear, just above the cochlea are three semicircular canals. Semicircular canals 22 of 49

23 35 4 Continue to: - or - Click to Launch: 23 of 49

24 35 4 The sensory receptor that detects variations in body temperature is a a. chemoreceptor. b. mechanoreceptor. c. thermoreceptor. d. photoreceptor. 24 of 49

25 35 4 The part of the eye containing tiny muscles that adjust the size of the pupil is the a. cornea. b. iris. c. lens. d. retina. 25 of 49

26 35 4 The part of the ear that produces the nerve impulses sent to the brain is the a. tympanum. b. Eustachian tube. c. cochlea. d. oval window. 26 of 49

27 35 4 The structures in your ears that help maintain your sense of balance a. is the auditory canal. b. is the hammer. c. is the tympanum. d. are the semicircular canals. 27 of 49

28 35 4 Photoreceptors in the eye that are sensitive to color are a. rods. b. cones. c. rods and cones. d. the optic nerve. 28 of 49

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