Chapter 8 - Special Senses
Special Senses Include
Smell
Taste
Sight
Hearing
Equilibrium
Special Sense Receptors
Large and complex sensory organs
Localized clusters of organs
Types of Receptors
Mechanical Receptors
Chemical Receptors
Photosensitive Receptors
1
,2
,↑ Chapter 8 - Special Senses
The Eye and Vision
70% of all sensory receptors are in the eyes
Each eye has over 1 million nerve fibers carrying information to the brain to the occipital
lobe (visual cortex)
The eye is located in the orbital cavity
Accessory structures include the
Extrinsic Eye Muscles (Smooth muscles)
Six muscles attach to the outer surface of the eye · Produce gross eye movements · Muscles of
Eyelids
Conjunctiva
Membrane that lines the eyelids and eyeball · Connects with the transparent cornea · Secretes
Lacrimal apparatus
Lacrimal gland + Ducts · Lacrimal gland (Exocrine gland): Produces lacrimal fluid (tears); situat
3
, External and Accessory Structures
Eyelids
Meet at the medial and lateral commissure (canthus, corners of the eye)
Eyelashes
Tarsal glands produce an oily secretion that lubricates the eye
Ciliary glands are located between the eyelashes, they affect lubrication and protection
The Structure of the Eye
4
Special Senses Include
Smell
Taste
Sight
Hearing
Equilibrium
Special Sense Receptors
Large and complex sensory organs
Localized clusters of organs
Types of Receptors
Mechanical Receptors
Chemical Receptors
Photosensitive Receptors
1
,2
,↑ Chapter 8 - Special Senses
The Eye and Vision
70% of all sensory receptors are in the eyes
Each eye has over 1 million nerve fibers carrying information to the brain to the occipital
lobe (visual cortex)
The eye is located in the orbital cavity
Accessory structures include the
Extrinsic Eye Muscles (Smooth muscles)
Six muscles attach to the outer surface of the eye · Produce gross eye movements · Muscles of
Eyelids
Conjunctiva
Membrane that lines the eyelids and eyeball · Connects with the transparent cornea · Secretes
Lacrimal apparatus
Lacrimal gland + Ducts · Lacrimal gland (Exocrine gland): Produces lacrimal fluid (tears); situat
3
, External and Accessory Structures
Eyelids
Meet at the medial and lateral commissure (canthus, corners of the eye)
Eyelashes
Tarsal glands produce an oily secretion that lubricates the eye
Ciliary glands are located between the eyelashes, they affect lubrication and protection
The Structure of the Eye
4
