A&P Ch.16 SB & Quiz

Which are true of rods?

- There are more than 100 million rod cells per eye - They function well in dim light

Which events occur during bright light adaptation?

- cones gradually adjust - rods become inactive - pupils constrict

When the ______ membrane moves, the _____ on the spiral organ hair cells distort because they are anchored by the tectorial membrane.

-basilar -stereocilia

The auditory sensory axons of the ____ branch of cranial nerve number _____ terminate in the cochlear nucleus within the brainstem.

-cochlear -8

Sensory receptors in which structures help monitor and adjust our equilibrium?

-saccule -utricle -semicircular ducts

Order these structures from superficial to deep. Start with the outermost structure first. sclera, neutral layer of retina, pigmented layer of retina , choroid

-sclera -choroid -pigmented layer of retina -neutral layer of retina

Optic tracts extend to which structures after they leave the optic chiasm?

-the lateral geniculate nucleus of the thalamus -superior colliculi

Receptors of the human body convert stimulus energy into ______.

An electrical signal -energy transduction

Where would you find olfactory hairs?

At the apical surface of olfactory neurons

The optic disc is associated with ______.

Cranial nerve II (the optic nerve)

What part of the retina is responsible for the sharpest vision?

Fovea centralis

Place the structures of the vascular tunic in order from anterior to posterior.

Iris, ciliary body, choroid

These receptors respond to touch, pressure, vibration, and stretch.

Mechanoreceptors

Which of the following is not one of the three criteria used to describe receptors?

Stimulus strength (intensity of stimulus)

Hearing and equilibrium are transmitted along which cranial nerve?

VIII (vestibulocochlear nerve)

What chamber is between the iris and cornea?

anterior chamber

Arrange the middle ear bones from lateral to medial. a: Stapes b: Incus c: Malleus

c,b,a

Receptors initiate sensory input to the ______.

central nervous system

Gustatory cells are ______.

chemoreceptors

What structure is filled with pigment from melanocytes?

choroid

Which structure of the eye absorbs light to prevent it from scattering within the eye?

choroid

What type of photoreceptors detects color?

cones

As we adjust to low light, our ______ becomes nonfunctional and it may take ______ for rhodopsin to become regenerated sufficiently so that you can see well in low-light conditions.

cones 20-30 min

The proper sequence of eye layers from the outermost to the innermost layer is a: Neural tunic b: Fatty tunic c: Vascular tunic d: Fibrous tunic

d, c, a

When you go from a bright light environment to a dark environment, you have a slow sensitivity to low light levels. This is called ______ ______.

dark adaptation

Light rays are refracted or bent when they pass through two media of different ______.

densities

Which papillae, distributed on the anterior two-thirds of the tongue surface, lack taste buds?

filiform

Pain is an example of a ______ sense.

general

The term equilibrium refers to our awareness and monitoring of our _____ position.

head

When light strikes a photoreceptor it

hyper-polarizes and releases less neurotransmitter.

What structure is the dividing line between the anterior and posterior chambers?

iris

A flattened lens

is necessary for distant vision

The process by which your eyes adjust from low light to bright light conditions is ______.

light adaptation

The otolithic membrane is part of the

maculae of the inner ear

Tactile receptors are a type of ______.

mechanoreceptors

These receptors respond to pain caused by external and internal stimuli.

nociceptors

Optic tracts ultimately are directed to the primary visual cortex in the ______ lobe.

occipital

A photopsin is a protein

of a photopigment within cone photoreceptors.

What part of the retina lacks photoreceptors?

optic disc

A lack of photoreceptors in this structure creates the "blind spot"?

optic disk

Olfactory receptors ______.

perceive odors

The external ear is located mostly on the outside of the body, while the middle and inner ear areas are housed within the _______ part of the temporal bone.

petrous

If stimulated over a period of time, _________ receptors lose eventually sensitivity.

phasic

What type of receptor can undergo adaptation?

phasic

The iris controls the size of the ______.

pupil

Most of the eye is ______ the orbit of the skull.

receded into

The area that a receptor cell gathers information from is called the ______.

receptive field

Some individuals experience pain in their left shoulder during a heart attack. This is an example of ______.

referred pain

______ occurs when impulses from an organ are perceived as originating from the skin.

referred pain

What structure is the "white" of the eye?

sclera

The part of the cochlea that converts pressure waves (from sounds) into changes in membrane potentials is the

spiral organ

The conjunctiva is composed of _____ epithelium.

stratified columnar, stratified squamous

Mechanoreceptors located in the skin and mucous membranes are called ______ receptors.

tactile

The most numerous type of receptor in the body is the

tactile receptor.

The middle and inner ear are housed within the _____ bone.

temporal

The middle and inner ear are in which bone?

temporal bone

The classification of a receptor as a photoreceptor or a mechanoreceptor depends on

the modality of the stimulus it perceives.

Where are photoreceptors located?

the neutral layer of the retina

Because numerous cutaneous and visceral sensory neurons conduct signals on _______ ascending tracts of the spinal cord, the brain sometimes falsely localizes the location of a pain stimulus.

the same

Gustation is the sense of

to taste

Which are the characteristics of the cornea?

transparent and avascular

Receptors for general senses are distributed throughout the ______ and viscera.

skin

Localization and sensitivity are easily determined in a ______ receptive field.

small

Olfaction is the sense of ______.

smell

Taste buds are found on the tongue and ______.

soft palate

The least numerous but the largest of the papillae are arranged as a V-shape on the posterior dorsal surface of the tongue. They contain the majority of taste buds and are called _____ papillae.

vallate

Which part of the eye is an attachment site for extrinsic eye muscles?

sclera

Which are a part of the fibrous tunic?

sclera and cornea

Which layer of the eye contains the blood and lymph vessels?

vascular tunic

Hearing and our sense of balance comes from the stimulation of which cranial nerve?

vestibulocochlear

The limbus is the junction between the sclera and the ______.

cornea

The apparent distortion of the spoon in the water glass is due to the phenomenon called

refraction

What structure makes up the posterior 5/6 of the fibrous tunic?

sclera

True or false: The eye is spherical, measuring about 5 centimeters in diameter, and most of it is receded into the orbit of the skull.

False