exam 4 Flashcards
what organisms do you see that have single lenses eyes that are with the cephalopods and vertebrates?
mollusks and spiders
how many lenses do cephalopods and vertebrates have?
one
what helps focus images in the eye?
cornea and lens
what does the cornea do?
lets light into eyes
what does the lense do?
it bends light and focuses it into the retina
what does the retina do?
it contains the photoreceptors
where is the retina located?
the innermost layer of the eyeball
what nerve cell carries information to the brain from the eyes?
optic nerve
what are the two types of receptor cells?
rods and cones
what are rods?
receptor cells that allow you to have night vision
what are cones?
receptor cells that allow you to have color vision
what do rods contain?
pigment, rhodopsin, that bleaches, and when it is bleached turns into retinal and opsin when light causes an action potential
how many subclasses of cones are there?
3
what is olfaction-chemoreception?
mostly air borne odors but some in liquid
what is the most sensitive organism to olfaction?
silk worm moth Bombyx mori
the male only senses odors with what?
feathery antennea
what is vertebrate olfaction?
what humans smell
what is the oldest sense?
vertebrate olfaction
what is the most sensitive vertebrate we know?
salmon
how does a snakes olfaction differentiate?
gather airborne molecules by moving tongue into Jacobson’s organ
what is the specialized receptor that helps insects listen?
tympanic membrane that vibrates due to sound waves. interpreted by ganglion
where is the audition located in vertebrates?
the ears
what has the most acute audition sense?
mammals
how many hertz can humans hear?
16,000-20,000
how many hertz can dogs hear?
30,000
how many hertz can bats hear up to?
100,000
what is the canal to the tympanum filled with?
wax and air
what does the middle ear consist of?
malleus incus and stapes
what does the inner ear do?
converts the sound waves to nerve impulses.
where is the cochlea located?
inner ear
how does the inner ear work
sound waves cause cochlear fluid to move hair cells brush against tectorial membrane causing hair cells to trigger an action potential
what insect has the best sense of taste?
dung beetle
what basic flavors do vertebrates taste?
salty, sweet, bitter, sour, umami
do all taste sensations come from all regions of the tongue?
yes
what are photoreceptors?
receptors that respond to light energy
what are chemoreceptors?
receptors that resond to chemical substances
what are mechanoreceptors?
receptors that respond to movement or physical stress
what are thermoreceptors?
receptors that respond to heat and or cold
what are generalized receptors?
receptors found in the skin dermis or they are deep receptors found in internal body structures
what are root hair plexuses?
neurons that wrap around the roots of hairs.
what type of receptor is a root hair plexus?
on/off
what are touch receptors?
receptors that have a receptive field and depending on the location differ in size
what are specialized receptors?
photoreception and chemoreception
what type of phototaxis do planaria experience during light?
negative phototaxis