stuff I dont know for anatomy

What is located in the fibrous layer?

Sclera and cornea

Sclera function

white tough outer layer

Cornea function

clear curved front surface, refracts light to retina

What makes up the vascular layer?

Choroid, ciliary body and iris.

Choroid function?

blood vessels and pigment to absorb strong light

ciliary body function

Changes the lens shape for focusing and produces aqueous humor. When the ciliary muscle contracts the lens rounds for near vision; when it relaxes the lens flattens for distance vision

Iris

colored part of eye, controls pupil size

What does the pupil do?

Opening in center of iris, allows light into the eye and contains the smooth muscles of the iris.

What makes up the neural layer?

retina, rods & cones, and bipolar and ganglion cells

What makes up the retina layers?

pigmented layer and neural layer

What does the pigmented layer do?

Absorbs light

what does the neural layer in the retina contain?

photoreceptors that detect and process light

What part of the eye contains the sharpest vision?

Fovea centralis

What is in the central area of the retina with high cone density?

Macula lutea

Why do you have a blind spot?

Where optic nerve exits eye, also no photoreceptors there

What does the lens do?

Focuses light on retina

What ligaments relate to the lens?

Suspensory ligaments attaching it to the ciliary body

What does the anterior cavity consist of?

aqueous humor that nourishes the cornea and lens.

How is the anterior cavity drained?

Canal of schlemm

What does the posterior cavity consist of?

vitreous humor that holds the retina in place

What divides the two chambers in the anterior cavity?

The iris divides them.

What portion of the body does the anterior ramus innervate?

Anterior portion of muscles and skin of body.

What portion of the body does the posterior ramus innervate?

Posterior portion of muscles and skin of body.

How many pairs of spinal nerves are there?

31

What does the cervical plexus consist of?

C1-C5 vertebrae, phrenic nerve.

What does the brachial plexus consist of?

C5-T1 vertebrae, axillary, radial, musculocutaneous median and ulnar nerves

What does the lumbar plexus consist of?

L1-L4, obturator nerve

What does the sacral plexus consist of?

L5-S4, sciatic nerve

Which is the faster nerve, proprioceptive nerves or pain and temperature related nerves?

proprioceptive nerves are faster.

What is referred pain?

stimuli that are perceived as cutaneous pain along a dermatome

Where are the rods located?

Peripheral retina

Does the fovea centralis contain rods or cones?

It contains cones

What do bipolar cells synapse with?

They synapse with photoreceptors

What do ganglion cells synapse with?

They synapse with bipolar cells

What is the order of light through the eye?

Ganglion→bipolar→photoreceptors→rods & cones

What makes up a photoreceptor?

outer and inner segment

cell body

synaptic terminal

What makes up the outer segment?

discs with photopigment molecules

What are the photopigment discs made of?

Rhodopsin

What makes up Rhodopsin?

Opsin and retinal

What are optic radiations?

axons from the thalamus that project to primary visual cortex

What is stereoscopic vision?

Depth perception created by overlapping visual fields

What makes ear wax?

Cerumen

What is the function of the tensor tympani?

Reduces vibration of the malleus

What is the function of the stapedius?

Reduces vibration of the stapes

What are the 3 cochlear ducts?

Scala vestibuli, scala media and scala tympani

What membrane separates the vestibuli and media ducts?

Reissner’s(vestibular) membrane

What membrane separates the media and tympani ducts?

Basilar membrane

Which cochlear ducts drain perilymph?

Scala vestibuli and scala tympani

What does the tympanic membrane do?

Separates the outer ear from the middle ear

What does the oval window do?

pushes fluid in cochlea which vibrates basilar membrane

What 2 structures does the vestibule contain?

Utricle and Saccule

What do the utricle and saccule do?

detect head tilting and linear movement.

What structure is found in the utricle and saccule?

Macula

What structure is found in the macula?

It contains receptors for head position and movement called hair cells

What are the structures on the receptor tips on the macula?

kinocilium and the stereocilium

where are the kinocilium and the stereocilium found?

In the otolithic membrane, suspended in endolymph

What happens when the head is tilted right?

stereocilium moves towards the kinocilium, hair cells depolarize and more glutamate is released

What happens when the head is tilted left?

stereocilium moves away from the kinocilium, hair cells hyperpolarize and less glutamate is released

Which membrane supports the organ of hearing?

The basilar membrane supports the Organ of Corti

What is frequency?

The number of vibrations/s

What is the unit for pitch?

Hz

What is the unit for loudness?

dB

What portion of the basilar membrane detects high pitch?

the narrow/stiff Base

What portion of the basilar membrane detects low pitch?

The wide/flexible Apex

What determines loudness?

The degree of displacement and number of hair cells stimulated

What determines pitch?

The location of the vibration

What is the helicotrema?

An opening where the scali vestibuli and tympani connect

What is the role of outer hair cells?

They amplify and fine tune sound

What happens in depolarization in ear?

K+ moves in

Why might som happens someone have conduction hearing loss?

issue getting sound to inner ear

What is an example of a muscle spindle reflex?

Knee-jerk reflex/patellar reflex

True or False, the flexion and crossed extension reflex is a polysynaptic reflex?

True

What are examples of a cranial nerve reflex?

Gag and corneal blink reflexes

Where are sympathetic preganglionic neurons found?

lateral horns of thoracic and lumbar region

What are white rami communicantes?

Myelinated axons of sympathetic preganglionic neurons that carry signals from the spinal nerve into the sympathetic chain ganglia

What are collateral ganglia?

Autonomic sympathic ganglia near the neurons’ target organs

What are splanchnic nerves?

A group of nerves in the sympathetic nervous system that transmit signals to abdominal viscera

What are grey rami communicantes?

Nonmyelinated axons that exit the ganglia

What are some types of cholinergic receptors?

muscarinic and noctinic

What do Beta Blockers do?

They are antagonists that bind to the heart and decrease their rate.

What innervates the adrenal medulla?

The preganglionic sympathetic neurons

What neurons make up the PSNS?

Cranial and Sacral neurons

What are the main parasympathetic nerves?

2 Vagus nerves

What 4 glands have active secretion while the PSNS is active?

lacrimal gland

mucus production

salivary glands

digestive tract glands

What is autonomic tone?

Constant amount of activity exhibited by each branch of ANS on target cell

Where are sympathetic tones dominant?

Blood vessels

Where are parasympathetic tones dominant?

The heart

What are 3 functions controlled by the reticular formation?

respiratory rhythm

the sleep/wake cycle

acid-base balance

What is static equilibrium?

Ability to maintain balance when head and body are not moving

What is dynamic equilibrium?

The ability to maintain balance during linear or rotational acceleration for head or body.

What fluid is found in the semicircular ducts?

Endolymph is found in them

What is the name of the enlargement in the semicircular ducts?

Ampulla

What gelatinous structure surrounds the stereocilia and the kinocilia?

Cupula

How do the semicircular ducts detect movement?

endolymph lags behind and pushes the cupula, bending the stereocilia

Why are vestibular signals sent to cranial nerve nuclei?

Coordinate eye movement in response to head movement