A&P Chapter 13, 15, 16

A structure that is located at the medial angle of the eye and contains glands that contribute to a gritty deposit is the

lacrimal caruncle

The hair cells of the utricle and saccule are clustered in

maculae

Each gustatory cell extends ________ (or taste hairs) into the surrounding fluids through a narrow taste pore.

microvilli

The olfactory receptors are highly modified

neurons

function of tears

nourishes the cornea and conjunctiva washes away debris provides oxygen lubricates the eye

Which cranial nerves have motor functions only?

oculomotor, trochlear, abducens, accessory, hypoglossal

The cranial nerves that innervate the eye muscles are

III, IV, and VI

Some neural tissues retain stem cells and thus the capacity to divide and replace lost neurons. Which of these special senses can replace its damaged neural receptors?

olfaction

Which cranial nerve carries visual information from the eyeball to the brain?

optic nerve

Which cranial nerves are involved with the eye?

optic, oculomotor, abducens, and troclear nerves

The hair cells of the cochlear duct are located in the

organ of Corti

Stimulation of nociceptive receptors within the trigeminal nerve might produce a perception of

peppery hot

Taste receptors are distributed in which of the following places?

surface of the tongue portions of the pharynx surface of the epiglottis

primary taste sensations

sweet, sour, bitter, salty, umami

Trace the gustatory pathway from the taste receptors to the cerebral cortex

taste receptors — facial, glossopharyngeal, and vagus nerves — synapse in the solitary nucleus of the medulla oblongata — medial lemniscus — synapse in the thalamus — gustatory cortex of the insula

The structure that overlies the organ of Corti is the

tectorial membrane

Perception of gravity and linear acceleration depends on

the force exerted by otoliths on hair cells of the maculae in the utricle or saccule

What is the function of the auditory tube?

to allow pressure equalization on both sides of the tympanic membrane

Jean needs to have a tooth in her mandible filled. Her dentist injects a local anesthetic to block pain afferents in one of her cranial nerves. What cranial nerve does the dentist numb?

trigeminal

Sound waves are converted into mechanical movements by the

tympanic membrane

The external ear ends at the

tympanic membrane

The auditory ossicles connect the

tympanic membrane to the oval window

Which of the following anatomical sequences is correct?

tympanum - malleus - incus - stapes - oval window - round window

The taste sensation that is triggered by the amino acids and small peptides is known as

umami

Difficulty in swallowing may be a sign of damage to which cranial nerve(s)?

vagus and glossopharyngeal

Where are the hair cell receptors for equilibrium located?

vestibule and semicircular ducts

The Roman numeral VIII indicates the ________ nerve

vestibulocochlear

Regarding the events involved in hearing:

vibration of the basilar membrane causes vibration of hair cells against the tectorial membrane

Where are visual images perceived?

visual cortex of the occipital lobe

When analyzing sound waves in the ear, the number of hair cells stimulated is interpreted as which characteristic?

volume

Which of the following symptoms would you associate with damage to the spinal accessory nerve?

weakness of the sternocleidomastoid muscle

The frequency of a perceived sound depends on

which part of the cochlear duct is stimulated

Define otoliths

They are densely packed calcium carbonate crystals that sit upon the gelatinous otolithic membrane in the maculae

Which of the cranial nerves is named for the fact that it "wanders," that is, innervates structures throughout the thorax and abdomen?

X

The first step in the process of photoreception is

absorption of a photon by a visual pigment

Visual pigments undergo which three changes during photoreception?

activation, bleaching, and reassembly

Hormones known as "catecholamines" are

amino acid derivatives

The sensory receptors of the semicircular canals are located in the

ampullae

Which of the following descriptions best matches the term stereocilia?

bending these produces receptor potential in hair cells

What are the two configurations of retinal?

bent 11-cis form and the linear 11-trans form

The ________ is a region of dense bone that surrounds and protects the membranous labyrinth

bony labyrinth

The abnormality that develops when a lens loses its transparency is known as

cataracts

Olfactory information is first received by which part of the brain?

cerebrum

The sensory neurons within the olfactory organ are stimulated by ________ in the air

chemicals

________ cells connect photoreceptors to ganglion cells.

Bipolar

Which statement correctly describes the process that occurs when light strikes a visual pigment?

Bleaching occurs when the rhodopsin molecule breaks down into retinal and opsin

Identify the structure that regulates the amount of light entering the posterior segment of the eye

Iris

Olfactory glands

coat the olfactory epithelium with a pigmented mucus

Where is the spiral organ located?

cochlea of the internal ear

Peptide hormones are

composed of amino acids

The ________ covers most of the exposed surface of the eye

conjunctiva

Identify the areas that are filled with aqueous humor.

The anterior and posterior chambers

A ray of light entering the eye will encounter these structures in which order?

cornea - aqueous humor - lens - vitreous body - retina - choroid

Define focal point

Focal point is the point at which the light rays from an object intersect on the retina

vitreous body

Holds the retina against the choroid Transmits light Supports the posterior surface of the lens

________ are chemical messengers that are released in one tissue and transported in the bloodstream to alter the activities of specific cells in other tissues.

Hormones

_______ fills the membranous labyrinth

endolymph

The formal term for the sense of gravity, rotation, and linear acceleration is the sense of

equilibrium

Identify the accessory structures of the eye

eyelids, eyelashes, the superficial epithelium of the eye, and the structures associated with the production, secretion, and removal of tears

An area of the retina that contains only cones and is the site of sharpest vision is the

fovea centralis

Light passing through the eye along the visual axis strikes what part of the retina?

fovea centralis

Gustatory receptors are found in the taste buds of all the following papillae

fungiform vallate foliate

The axons of which cells converge at the optic disc to form the blind spot?

ganglion cells

All target cells

have hormone receptors and can respond to chemical signals

Norepinephrine and epinephrine are considered to be ________ when released into the bloodstream, but ________ when released at synapses

hormones; neurotransmitters

A patient develops a tumor of a cranial nerve that leads to difficulty in speaking from a loss of tongue movement. Which cranial nerve is affected?

hypoglossal

Movement of the endolymph in the semicircular canals

signals rotational movements

You suspect your friend has damage to cranial nerve I when he is unable to

smell his food

Why does the near point of vision typically increase with age?

Elasticity of the lens decreases with age

The following steps occur in rods when they are excited by photons of light

1.) Retinal changes to a more linear form 2.) Opsin activation occurs 3.) Opsin changes the membrane permeability of the outer segment to Na+ 4.) Neurotransmitter release changes 5.) Ganglia cells detect changes in bipolar cell activity 6.) Rhodopsin breaks down (bleaches)

A typical gustatory cell survives for only about ________ days before it is replaced

10

There are ________ pairs of cranial nerves

12

The following is a list of the steps that occur in the production of an auditory sensation. 1. The pressure wave distorts the basilar membrane on its way to the round window. 2. Movement of the tympanic membrane causes displacement of the malleus. 3. Displacement of the stereocilia stimulates sensory neurons of the cochlear nerve. 4. Movement of the malleus causes movement of the incus and stapes. 5. Distortion of the basilar membrane forces the hair cells of the organ of Corti toward or away from the tectorial membrane. 6. Movement of the oval window establishes pressure waves in the perilymph of the vestibular duct. What is the proper sequence for these steps?

2, 4, 6, 1, 5, 3

The olfactory receptor cell can be activated by as few as ________ odorant molecules

4

Identify the fluid filled space between the cornea and iris

Anterior chamber

Which of the following structures is highly vascular?

Choroid

Identify the muscular structure that anchors the lens in place

Ciliary body

Identify the structure that allows light to first enter the eye

Cornea

During the process of olfaction, which molecular event occurs?

Cyclic AMP opens sodium channels in the plasma membrane

Compare olfactory receptors with receptors for the other special senses

Olfactory receptors are the dendrites of specialized excitable olfactory neurons, whereas the receptors for the other special senses are receptor cells with inexcitable membranes and form synapses with the processes of sensory neurons

Which of the following choices best describes the correct sequence of the nervous pathway structures for the sense of smell?

Olfactory receptors, olfactory bulb, olfactory tract, olfactory cortex

Which of the following regions is known as the blind spot?

Optic disc

In order to perceive a "smell," certain components must be present to transmit an olfactory message to the brain. Which of the following components is required?

Receptor proteins in the receptor cell membrane The enzyme adenylate cyclase Cyclic AMP opening sodium channels in the receptor membrane

Compare rods with cones

Rods are active in dim light, and objects appear black and white. Cones require intense light, and objects appear in color.

For distant vision, which event is true?

The ciliary muscle relaxes

Which of the following statements most accurately describes the olfactory organ that allows us to detect odorants we come in contact with?

The olfactory epithelium contains millions of modified neurons with multiple cilia-like dendrites that project into the surface mucus layer.

Describe the structural classification of hormones

The structural classification of hormones divides them into amino acid derivatives, peptide hormones (built from amino acids as prohormones), and lipid derivatives (built from fatty acids or cholesterol).

What is the common goal of the nervous and endocrine systems?

To coordinate and regulate the activities of other cells, tissues, organs, and organ systems

Only the fibrous layer can be observed in its entirety from the superficial surface of the cow eye

True

The iris changes the diameter of the opening at its center, which is known as the pupil.

True

The lens divides the eye into the anterior segment, located in front of the lens, and the posterior segment, located behind the lens.

True

Which cranial nerve monitors all the taste buds located on the anterior two-thirds of the tongue?

VII

Where is the vitreous body located?

posterior segment

Identify the three types of cones

red, green and blue cones

Identify the neural layer

retina

A pigment synthesized from vitamin A is

retinal

In the retina, the correct sequence of neural wiring is

rod - bipolar cell - ganglion cell - thalamus

Gravity and linear acceleration are sensed in the

saccule and utricle

Name the largest portion of the fibrous layer

sclera

identify the parts of the fibrous layer

sclera and cornea