senses Flashcards
the chemical or electrical changes induced by a stimulus
sensation
what you do with the sensation
perception
skin, body surfaces, & skeletal muscles
somatic
in viscera
visceral
from environment
extertoteceptors
sensations from organs
interoreceptors
a sense organ in striated muscles, joints and tendons
proprioceptor
widely distributed
general sensory organs
localized specialized
special sensory organ
a type of general sensory sensory receptors that may arborize
- mainly pain, can be extreme hot or cold or touch
- no specialized organs
free nerve endings
enclosed in specialized structure
encapsulated
sensory ending wrapped in mesodermal cells- touch
meissners corpiscle
skin, joints, deep tissue (pancreas) – pressure
Pacinian corpuscles
terminus wrapped around another organ
-ex/ hair
associated
From information gathered in muscles, tendons, and joints
-limb flexion and degree of muscle contraction
proprioception
specialized striated intrafusal muscle cells
-maintain muscle tone
intrafusal muscle cells
-muscle spindles
relaxed state
tonus
Relax too much – detect sag – reflex sent to extrafusal cells
Also sense stretch
muscle spindles
record tension in organs
golgi tendon organs
control smell and taste
chemoreceptors
tastebuds are absent in what
Hagfish
tastebud distribution in mammals
sill has orophrynx but mainly tongue aiwht some on epiglottis, soft palate and pharynx
– pain/temperature receptors – spicy
pungency
mint, menthol, cold receptors
coolness
tingling from Sichuan Pepper
Numbness
puckering – unripe fruit, tannins, wine
Astringency
galvanic reaction
metallicness
chalkiness
calcium
specialized patch of epithelium that captures chemicals
olfactory epithelium
have tuft of sensory cilia (apical)
(basal) axon through cribiform plate to
olfactory sensory
mitral cells send long axons to rest of brain (olfactory tract) to piriform lobe and septum
olfactory bulb (brain)
the new internal naris in Osteolepimorphs allows
breathing and smell to be linked
Nasal Sac Enlarges, Separate recess – Vomeronasal (Jacobsen’s) Organ
amphibians
Nasal Sac Very large, Extensive terminals, olfactory epithelium back, rest respiratory
mammals
Internal Choana
Osteolepimorph
Nasal sac differentiated, some with Conchae (turbinals), Jacobsen’s organ separate, Birds with scroll-like conchae
reptiles
vomeronasal organ in squamates
tongue flicking
many fish, reptiles and birds can detect
UV light
vampire bats, pythons and pit vipers can detect
IR
concentrate light on photoreceptive tissue (retina)
eye
low light sensors
-sense black and white
rods
detect colors
cones
focusing
visual accomodation
- focusing and protection – portion of sclera that becomes clear
cornea
Tough capsule of connective tissu
-helps define shape
extrinsic eye muscle
help reptiles and fish hold shape
scleral ossicles
largest, highly vascularized, support
Nocturnal animals – tapetum lucidum – reflects light
choroid
– tiny circle of smooth muscle
controls accommodation
Attached to lens by suspensory ligament (circular)
ciliary body
smooth muscle
iris
hole in center
pupil
innermost layer
retina
middle layer
uvea
outer layer
sclera
in some retina, indented point where light converges
fovea
-sharpest focus
Filled with transparent fluid that helps maintain shape
chambers
watery in front of the eye
aqueous humor
anterior and posterior chamber
Vitreous Humor – viscous
Sometimes called vitreous body
Vitreous chamber
development of eye
- optic vesicles
- optic placode
- optic placode-> lens primordium
- optic vesscle->optic cup
- mesenchyme surrounds eye
choroid and sclera
mesenchyme
eyelid, cornea, lens
ectoderm
optic nerve
optic stalk
No cornea, lens or melanin Primitive photoreceptors (wired directly to ganglion cells)
hagfish
Has pigment spot
amphioxous
had the earliest focusing eye
-camera lens
lamprey, chondrichthys
clear skin on front of cornea in lampreys
spectacle
mucles attached direclty to lens in chondrichthys
protractor lentis
lens spherical and held by syspersory ligament
chondrithyes and bony fish and amphibians
muscles attached directly to lens in bony fish
retractor lentis
circular suspersony ligament stretches lens
amiotes
not analogous to camera lens
amniotes
blood vessels to supports retina
papillary cone in nonavian reptiles
pecten in birds
dim light rods
scotopic
bright light, color, cones
photopic
earliest verts has what kind of vision
tetrachromic
amphibian ision
lack cones- trichromic
mammals
dichromic
old wold monkeys
trichromic (us)
new world monkeys
females-dichromic if homo
trichromic if hetero
pineal organ or gland
epiphysis
with parietal foramen so parietal organ
ostracoderms
epiphysis and parietal organ with some photosensitivity
lampreys
Epiphysis prominent
Parietal Organ – absent or rudimentary
jawed fish
Epiphysis and Parietal Organ – generally both present primitively
amphibians
Distinct parietal eye in fossil
lissamphibia
Epiphysis and Parietal Organ –both present
Distinct third eye
lizards and tuataras
Lateral Line Sense, vestibular apparatus, hearing
Based on Hair Cells
mechanoreceptors
- Microvilli – projections of unequal length, nonmobile
stereocilia
one long cilium
kinocilium
Stereocilia + Kinocilium
hair bundle
Collection of hair and supporting cells
Neuromast Organ
Projecting hair bundles usually embedded in gelatinous cap
capula
-increase sensitivity
called distant touch
-may pick up some sound waves
lateral line sense
balace organ
vestibular apparatus
the vestibular apparatus may contain
oroliths or smaller otoconia (mammals)
A specialized region for hearing
Lagena
-coiled in mammals called cochlea
Specialized strip of neuromasts connected via VIII
organ of corti
tube (particularly long in birds and mammals)
external auditory meatus
therians add what for directional heating?
pinnae
middle ear
typanum
remains of cavity remains open to pharynx
Eustachian Tube
vestibular apparatus (balance organ) and lagena
inner ear
translates sounds in air to sounds in water
-also amplifies sound
ossicles
addition of middle ear
tympanic ear
-evolved 5x
chewing noises transferred through
auditory chain
