Chapter 23 + 24- General & Special Senses Flashcards
What are general sense receptors?
Temperature- free nerve ending (most widely distributed)
Pressure/touch
- tactile (Meissner corpuscle)
- Lamellar (Pacini Carpuscle)
Pain- free nerve ending
Free nerve endings are nerves ending in small hairs without organs
What are the 5 special senses?
Smell (olfaction)
Taste (gustatory)
Sight
Hearing
Equilibrium
What is the olfaction purpose and how does it work?
Smell
Chemoreceptors on roof of nasal cavity detect chemical changes and fire action potential by the Cranial Nerve I to the brain
What is the gustatory sense?
Taste
What are the three kinds of papillae and what are their purpose? Where are they found?
Fungiform- front of tongue. Taste buds
Circumvallate- back of tongue. Taste buds
Filiform- between fungiform and circumvallate. No taste buds. Perceive texture
What is the purpose of taste buds?
Taste buds house the gustatory chemoreceptors whose hairs are stimulated when chemicals dissolve in saliva
Each taste bud responds most effectively one of the five primary taste sensations
- sour
- sweet
- bitter
- umami (savoury)
- salty
What nerves are part of the gustatory sense?
Facial nerve- CN VII
Glossopharyngeal nerve- CN IX
Vargas nerve- CN X
What is a sense organ and what are their purpose?
Organs that enable the body to respond to stimuli caused by changes to internal or external environment
Two types- general and special
Which organ is responsible for two senses?
Ear
Hearing and equilibrium
What are the sensory receptors in the ear?
Mechanoreceptors
Respond to touch and sound
What are the components of the outer ear?
Pinna (auricle)- cartilage part
External auditory canal
- narrow chamber lined with skin
- location of ceremonious glands
- ends at tympanic membrane (ear drum)
Outer ear is responsible for hearing only, not equilibrium
What are the components of the middle ear?
Air filled cavity
Three auditory ossicles
-Malleus moves when ear drum vibrates and strangers sound to inner ear through ossicles
Middle ear opening
What are the three auditory ossicles called?
Malleus (hammer)
Incus(anvil)
Stapes (stirrup)
What are the openings of the middle ear?
Opening from external acoustic Mateus (ear canal) is covered by tympanic membrane
Oval window- stapes sits over this
Round window- covered by membrane. Below oval window
Auditory tube- opening that connects middle ear with throat (allows for pressure equalization during yawning and swallowing)
What is the fluid that fills the inner ear called?
Perilymph
What Is The bony labyrinth?
Maze of bony chambers in the inner ear, making up the
Vestibule (balance)
Cochlea (hearing)
Semicircular canals (balance)
What is the membranous labyrinth?
Within bony labyrinth.
Inside vestibule (balance) Cochlea (hearing) Semicircular canals (balance)
What is the fluid that fills the membranous labyrinth called?
Endolymph
What is the organ of corti?
Hearing organ within the membranous cochlea
Walls of cochlea membrane (basilar membrane) in the organ of corti have hairs that move to detect sound
What are the two nerves in the inner ear that help with hearing and what nerve do they make up?
Vestibular and cochlear
Make up the vestibulocochlear nerve CN VIII
Nerve impulses sent to auditory cortex
What are the two types of equilibrium and what is their purpose?
Static equilibrium- ability to sense position of head relative go gravity as well as acceleration/deceleration
Dynamic equilibrium- balance while moving
What are the macula and how do they work?
Receptors in the vestibule of the inner ear
- reports position of the head
- hairs embedded in gelatinous otolithic membrane move/bend when pressure changes and relay information via vestibular nerve
What is the sense organ with the most sensory receptors?
The eye- 70% of all sensory receptors
What is the mucous membrane that sits in the eyelid?
Conjunctiva
connects to surface of eye and secretes mucous for lubrication
