CVA SENSORY

SENSORY receptor function

general term for cells that detect info about env.

SENSORY neurons

Specialized to transduce stimuli into action potentials

Chemoreceptors are sensitive to—

chemicals

Pheromones

chemical messages form 1 indv. to another

Fishes’ olfactory epithelium in—

paired nasal sacs and open @ ext. nares

Vomeronasal organ/ Jacobson’s organ location and function

Accessory olfactory system;

ass. w/ pheromones and prey detection; detecting non-volatile chemicals

Taste buds: epithelial struct. that holds chemoreceptors of taste are transmitted by—

CN VII + X + XII

Visible light is “visible” bc—

it’s detectable by human eyes

UV light is visible to many invert., fishes, birds, reptiles but very few—

mammals

In Infared lights, emanated from objects acc to their—

temperature

Rods are—

LOW light sensors

Cones are—

COLOR sensors

Free

“Naked” nerve endings; v sensitive for pain and temp

Encapsulated

Enclosed in struct that modifies transduction

Associated

Wrapped around another organ (ie hair follicles)

Fishes’ lens are—

nearly round + moved in/out to focus

Proprioception meaning

sense of body’s position in space

Vomeronasal organ is NOT found in—

fish, most turtles, archosaurs, and aquatic mammals

Where is the Vomeronasal organ in Amphibians?

in nasal cavity

Where is the Vomeronasal organ in Mammals?

in nasal cavity (when present)

Where is the Vomeronasal organ in Reptiles?

in mouth

Sclera is the

tough outer layer of the eye

Cornea is the—

clear front area of the sclera

Tapetum lucidum is the—

reflective layer in nocturnal species; “eye shine”

Ciliary body

circle of smooth muscle that focuses lens

Lens’ function

focuses light on retina

Iris’ function

muscle that opens/ closes pupil

Retina is the—

inner layer w/ photoreceptors

Fovea is the “pit” in the retina with the—

highest density of cones (highest focus)

The Optic never (CN II) is not really a nerve but rather—

an extension of the brain

Fishes’ eyeball(s) often supported by—

scleral ossicles or cartilages

Amphibians’ have no—

scleral ossicle but sometimes cartilages

Like fishes’ eye phylogeny, amphibian lens—

moved in/out to focus

Amphibian’s lens usually—

focused on distant objects

Compared to fishes and amphibians, Amniotes’ lens—

changes shape to focus (except for snakes)

No mammals possess—

scleral ossicles

All vertebrates possess rods, but not all vertebrates possess—

cones nor every known cone

Does visual range shorten in water than in air?

Yes

The earliest verts had—

tetrachromatic cones

Which does tetrachromatic cones consist of?

violet, blue, green, orange

What does trichromatic cones consist of?

blue, green, yellow

What does dichromatic cones consist of?

violet and orange

Which cone combo are most useful for nocturnal lifestyles?

Dichromatic

Monocular vision

Visual fields do not overlap

Binocular vision

Visual fields overlap

Stereoscopic vision

image w/in overlap of eyes

In binocular vision, signals from both eyes cross in optic chiasm, so—

both sides of brain process both eyes’ input

Parietal eye aka pineal eye aka 3rd eye is a—

Photoreceptive extension of epithalamus

IR emitted by anything warmer than—

absolute 0

With IR sight, visible light only seen when it—

reflects off of something

Mechanoreceptors respond to—

movement

Hair cell(s) is a common type of

mechanoreceptor

Neuromast are a—

collection of hair cells and supporting/assisting cells

Mechanoreception forms senses of—

touch, hearing, balance/equilibrium

Lateral line system is a—

mechanoreception sys for detecting water currents

“Distant touch” functions

Many fishes can detect nearby objects w/out actually touching

Low-f sounds function

Sound waves may be detected (same physical stimulus)

Lateral line sys are absent in—

terrestrial vertebrates

Derived from lateral line sys, the Vestibular apparatus—

senses motion, balance, and orientation w/ Fluid-filled spaces w/ hair cells that detect

Macula

Organs that detect orientation due to gravity

Lagena aka cochlea

Enlargement of sacculus specialized for hearing

The Lagena is derived from—

the Vestibular apparatus

Ext. ears are absent in—

fishes and amphibians

Pinna

Ext. flap on mammals

The ext. auditory meatus is also known as—

the Ear canal

Ossicles

Tiny bones that transmit sound to inner ear

Mammals, in number of ossicles, contain—

3 bones: malleus (articular), incus (quadrate), stapes (columella)

Electroreceptors detect—

electric fields

Ampullae of Lorenzini

Electroreceptors in sharks used in find prey