Do you know which 2 special senses are chemical in nature?

What classification of receptor would this be?

Taste and Smell are chemical in nature

Chemoreceptor. 

Do you know the anatomical name for eyelids?

What are their functions?

Palpebrae.

Protection of the eye. 

Do you know the function of the lacrimal caruncle?

do you know the other name for this substance? 

secretes a substance made from oil and sweat glands. 

Sandman's eyesand. 

Structures (in order that tears would encounter them): 

a. Lacrimal Gland- superolateral to the eye. Makes and secretes tears. 

b. Lacrimal Puncta- located on the upper and lower lids in the medial canthus. Drains tears.

c. Lacrimal Canaliculi- drains tears from the puncta into the lacrimal sac.

d. Lacrimal Sac- collects tears from the canaliculi and leads them into the nasolacrimal duct.

e. Nasolacrimal Duct- drains tears into the nasal cavity  

Structures (in order that tears would encounter them): 

a. Lacrimal Gland- superolateral to the eye. Makes and secretes tears. 

b. Lacrimal Puncta- located on the upper and lower lids in the medial canthus. Drains tears.

c. Lacrimal Canaliculi- drains tears from the puncta into the lacrimal sac.

d. Lacrimal Sac- collects tears from the canaliculi and leads them into the nasolacrimal duct.

e. Nasolacrimal Duct- drains tears into the nasal cavity  

Tears:

a. Function- lubricates eyes, flushes away debris, cleanses and protects the eye.

b. Composition- mucus (lubricates), lysozyme and antibody (both fight bacteria) 

Tunics: 

a. Fibrous Tunic- sclera and cornea. Sclera is strong and protective. Allows attachment of the muscles to the eye. The cornea is transparent and allows passage of light into the the eye. 

b. Vascular Tunic (uvea)- composed of the choroid, which is pigmented and contains vessels to nourish the eye, ciliary body and iris. The ciliary body is responsible for changing the shape of the lens and producing aqueous humor and the iris is responsible for controlling the size of the pupil. 

c. Sensory Tunic- contains a pigmented layer and a neural layer. The neurons that are stimulated by light and in this layer. 

Components:

a. Ciliary muscle- smooth muscle responsible for changing the shape of the lens.

b. Ciliary zonlue- small ligaments that attach the ciliary muscle to the lens.

c. Ciliary processes- make and secrete aqueous humor.

Can you describe and give the function for the pupil?

How is the size of this structure regulated? 

The pupil is a hole in the iris that allows light to pass into the eye.

The parasympathetic division constricts it and the sympathetic division dilates it. 

What types of cells are in the neural layer? 

a. What are the names of the 3 types of cells found here?

b. Of these cells, which one of them has axons that leave the back of the eye as the optic nerve? Which cranial nerve (number) is this?

Bipolar Neurons.

a. Photoreceptors, bipolar cells, and ganglion cells.

b. Ganglion. CN II. 

Do you know the 2 types of photoreceptors there are in the retina?

Can you describe them?

Types:

a. Rods- rod-shaped and are stimulated by low light levels. Vision is black, white and grayscale when using rods. 

b. Cones- cone-shaped and stimulated by higher levels of light. Vision is in color when using these. 

Macula lutea is the center of the retina that is concentrated with cones.

The fovea centralis is the area that has the highest concentration of cones within the macula lutea and is located at the posterior pole (direct center). 

Can you describe the organization of the anterior and posterior segments and chambers of the eye?

a. do you know what fluids are found in these compartments?

i. What is the function of these fluids?

The anterior segment is from the cornea to the lens and the posterior segment is from the lens to the back of the eye. The anterior segment is further divided into chambers: the anterior chamber is cornea to iris and the posterior chamber is iris to lens.

a. Aqueous humor fills the anterior segment and vitreous humor fills the posterior segment.

i. contributes to intraocular pressure and nourishes the eye. 

Biconvex structure. 

It is located between the anterior and posterior segments of the eye and suspended from the ciliary body by the zonule.

Its function is for accommodation (focusing) of light. 

Do you know what the organ for smell is?

Where is it located?

Olfactory Epithelia. 

On the superior nasal concha of the ethmoid bone in the roof of the nasal cavity. 

Can you list and describe the function for the 3 types of cells in the olfactory epithelium?

Cells:

a. Receptor Cells- bipolar neurons. Contain the receptors for smell.

b. Supporting Cells- pseudostratified epithelia that supports the neurons and may differentiate into neurons to replace damaged/dead ones.

c. Basal Cells- do mitosis and give rise to new supporting cells. 

Through what structure do the neurons for smell pass through to reach the olfactory bulb?

Collectively, what is the name of all of the neurons for smell (hint:cranial nerve)?

The olfactory foramina in the cribriform plate of the ethmoid bone.

Filaments of the cranial nerve I (olfactory nerve)

Can you define the following terms?

a. olfactory bulb

b. Olfactory tract

c. Glomerulus

Terms:

a. Olfactory Bulb- area on the brain that is the site for synapsing between the cranial nerve I and the mitral cells.

b. Olfactory Tract- axons of the mital cells in the CNS towards the thalamus.

c. Glomerulus- globe shaped structure that surround the synapse betweeb the mitral and olfactory cells (this is inside the bulb)

Can you define the follwing following terms?

a. Olfactory Bulb

b. Olfactory Tract

c. Glomerulus

a. Olfactory Bulb- area on the brain that is the site for synapsing between the cranial nerve I and the mitral cells.

b. Olfactory Tract- axons of the mitral cells in the CNS towards the thalamus. 

c. Glomerulus- globe-shaped structure that surrounds the synapse between the mitral and olfactory cells (this is inside the bulb)

what type of cell synapses with the olfactory cells?

Specifically, in which structure does this synapse occur?

Mitral.

Glomeruli of the Olfactory Bulb. 

what structure in the brain interprets the information for smeel?

what structure gives us appreciation of smells?

Uncus in the Temporal Lobe.

Limbic System. 

Odorants

Can you list and describe the 3 forms of pappilae in the mouth?

which of them have taste buds in them?

a. Fungiform- most numerous. Mostly on the tongue. Small and contain taste buds.

b. Circumvallate- form a "V" on the bacl 2/3 of the tongue. Large and contain buds.

c. Filiform- small and provide friction to the surface of the tongue. NO BUDS! 

Can you list and describe the function of the 3 types of cells found in a taste bud?

What classificatiom of tissue do these cells belong to?

a. Gustatory (taste) cell. Has "hairs" that protrude through the pore of the bud and contain receptors for tastants.

b. supporting cells- support the epithelia cells

c. Basal cells- mitosis

d. ALL 3 types are EPITHELIA CELLS

Sensations:

a. Salty- from ions such as sodium, potassium, chloride..

b. sweet- from carbohydrates

c- sour- from hydrogen ions

d. bitter- from alkaloids

e. unami- from glutamate (high in beef and aged cheese)

do you know what chemicals for taste are called? 

what do these chemicals require to be able to bind to their receptors on a gustatory cell?

Tastants

They require WATER. 

what structure in the brain interprets information for taste?

what structure gives us appreciation taste? 

Gustatory Cortex.

The Limbic System gives us appreciation for taste. 

Can you name the 3 parts of the ear?

a. which parts are for hearing and which are for equilibrium?

parts:

a. outer/external- hearing only

b. middle- hearing only

c. Inner/internal- hearing and equilibrium

Can you describe and give the function for the following outer ear structures?

a. Pinna

b. Lobule

c. external auditory meatus/canal

d. ceruminous glands

e. tympanum

structure:

a. pinna/auricle- outer ear flap. collects sound waves and funnels them into the canal.

b. lobule- part that we call the "earlobe". Made of fat and aerolar ct. 

c. external auditory meatus/canal- opening and tube into the ear.

d. ceruminous glands- secrete cerumen (wax) along the meatus/canal to trap debris.

e. tympanum- CT membrane that forms the boundary between the external and middle ear and transmits soundwaves to the ossicles. 

can you give a description and function for the following middle ear structures?

a. Pharyngotympanic tube

b. round window

c. oval wondow

d. ossicles

srtucture:

a. Pharyngotympanic tube- connects the middle ear to the throat (pharynx) to equlibrate pressure between the external environment and middle ear.

b. round window- CT membrane that is a boundary between the middle and inner ear.

c. oval window- CT membrane that is adhered to the Stapes bones and is a boundary to the inner ear.

d. ossicles- small bones in the middle ear. they transmit sound waves. 

can you define "bony labyrinth" and "membranous labyrinth"?

a. in which part of the ear are these structures found?

The bony labyrinth is a series of tunnels formed inside of the petrous region. it is filled with perilymph.

The membranous lambyrith is a series of membrane sacs inside of the bony lambyrith and is filled with endolymph. 

Chamber of the inner ear. 

the semicircular canals and the cochlea extend from it. 

can you list and describe the chambers of the cochlea? 

a. which of the chambers are filled with perilymph? endolymph?

chamber:

a. scala vestibule- its floor is the vestibular membrane. it is the superior chamber and is filled with perilymph.

b. scala media (cochlear duct)- its roof is the vestibular membrane and the floor is the basilar membrane. it is the middle chamber, is filled with endolymph and contains the organ of Corti. 

c. scala tympani- its roof is the basilar mebrane, it is the inferior chamber and is filled with perilymph. 

Roof- Vestibular Membrane

Floor- Basilar Membrane

what is the name of the organ for hearing? 

can you list the 3 types of cells found in this structure? 

Organ of Corti is the organ for hearing. 

the 3 cells are: receptor cells, supporting cells and basal cells. 

The hair cells for hearing would pass information in which nerve?

this nerve is a branch of which cranial nerve? 

Cochlear nerve (branch)

CN VIII.

NT is release to the fibers of the Cochlear nerve, which joints the Vestibular nerve to form from CN VIII.

CN VIII enters the medulla oblongota, and the information travels to the thalamus, then to the auditory cortices of the temporal lobe. 

do you know the difference between static and dynamic equilibrium?

a. which vestibular structures are used for each of these forms of equlibrium? 

static equilibrium is movements of the body in one plane of space (linear) and dynamic equilibrium is movements though all planes of space (rotary). 

a. the maculae of the vestibule are for static and the semicircular canals are for dynamic. 

can you describe the macula? what cells are found here?

which nerve receives information from the macula?

this nerve is a branch of which cranial nerve?  

Vestibular Nerve (branch)

CN VIII.

can you describe and give the function of for the crista ampilaris? 

a. what cells are found here?

b. what stimuli is this structure sensitive to?

a pad of cells (receptor cells with "hairs", supporting cells and basal cells) with a gel-like capula over it.

it is found in the ampulla (widened end of the canal). 

a gel-like mass over the crista ampullaris. the hairs of the receptor cells are embedded in it and are activated when the cupula moves with the movements of the head. 

which nerve receives information from the crista ampullaris?

this nerve is a branch of which cranial nerve?

Vestibular Nerve (branch)

CN VIII.