Lab 11 Flashcards
Name the skeletal muscles of the eyeball that innervate the following CN
Oculomotor
CN III
Superior, inferior, medial rectus, and inferior oblique
Name the skeletal muscles of the eyeball that innervate the following CN
Trochlear
CN IV
Superior oblique
Name the skeletal muscles of the eyeball that innervate the following CN
Abducens
CN VI
Lateral rectus
What structure is the colored part of one’s eye?
Iris
Function of the pupil
Control the amount of light entering the eye
Function of the lens
Focus the light to a specific region of the retina
What happens when the ciliary muscles contract?
- Narrows the circumference of ring
- Relaxes the suspensory ligaments
- Lens returns to resting shape – round and conducive to greater refraction and closer vision
Explain the blind spot
The presence of the optic disc prevents the retina from perceiving light in that area
Photoreceptor found at the fovea centralis and its impact on vision
Cones: come in one of three forms (red, green, or blue) and provide color vision and acuity
Name the Cranial Nerve and Function
CN I
CN: Olfactory
Origin: Cerebrum
Exit: Cribiform plate
Modality: Sensory
Function: Smell
Name the Cranial Nerve and Function
CN II
CN: Optic
Origin: Cerebrum
Exit: Optic Canal
Modality: Sensory
Function: Vision
Name the Cranial Nerve and Function
CN III
CN: Oculomotor
Origin: Brainstem
Exit: Superior orbital fissure
Modality: Motor
Function: Eye movement - inferior oblique, superior/ inferior/ medial rectus; pupil constriction
Name the Cranial Nerve and Function
CN IV
CN: Trochlear
Origin: Brainstem
Exit: Superior Orbital Fissure
Modality: Motor
Function: Eye movement – superior oblique
Name the Cranial Nerve and Function
CN V-1
CN: Trigeminal – Opthalmic
Origin: Brainstem
Exit: Superior orbital fissure
Modality: Sensory
Function: sensation in the face
Name the Cranial Nerve and Function
CN V-2
CN: Trigeminal - Maxillary
Origin: Brainstem
Exit: foramen rotundum
Modality: Sensory
Function: Sensation in the face
Name the Cranial Nerve and Function
CN V-3
CN: Trigeminal – Mandibular
Origin: Brainstem
Exit: Foramen Ovale
Modality: Both
Function: sensation in the face and chewing
Name the Cranial Nerve and Function
CN VI
CN: Abducens
Origin: Brainstem
Exit: Superior orbital fissure
Modality: Motor
Function: eye movement - lateral rectus
Name the Cranial Nerve and Function
CN VII
CN: Facial
Origin: Brainstem
Exit: Internal acoustic meatus > Stylomastoid
Modality: Both
Function: Taste; somatosensory info from ear; facial expressions
Name the Cranial Nerve and Function
CN VIII
CN: Vestibulocochlear
Origin: Brainstem
Exit: Internal acoustic meatus
Modality: Sensory
Function: Hearing and balance
Name the Cranial Nerve and Function
CN IX
CN: Glossopharyngeal
Origin: Brainstem
Exit: Jugular foramen
Modality: Both
Function: Taste; somatosensory from tongue/ tonsil/ phraynx; swallowing
Name the Cranial Nerve and Function
CN X
CN: Vagus
Origin: Brainstem
Exit: Jugular foramen
Modality: Both
Function: Taste; Regulation of internal organ functions and vasomotor activity (e.g. coughing, sneezing, swallowing)
Name the Cranial Nerve and Function
CN XI
CN: Accessory
Origin: Brainstem
Exit: Jugular foramen
Modality: Motor
Function: Movement of sternocleidomastoid and trapezius
Name the Cranial Nerve and Function
CN XII
CN: Hypoglossal
Origin: Brainstem
Exit: Hypoglossal canal
Modality: Motor
Function: Tongue muscles
Benefit of olfactory reflex
- harsh smells induce a withdrawal reflex to decrease the likelihood of ingestion/ exposure to harmful substances
Evolutionary advantage to adaptation to smell
- We are alerted to changes in proximity/ intensity of smells
- We can make cognitive decisions regarding odors
- Over time, these diminish so we only distinguish when conditions change
Why is solution necessary for taste?
- Gustation requires chemical ligands binding to ligand channels in the receptor membranes
- This requires sensed chemicals to be dissolved in the ECF surrounding the receptors
What is the exact region of the nasal cavity receptive to smell stimuli?
The muscosal membranes of the uperior border of the nasal cavity
How can we distinguish two similar smells?
Taste requires memory, texture, temperature
Name the cranial nerves that exit through the
Superior Orbital Fissure
Oculomotor (III), Trochlear (IV), Opthalmic (V-1)
Name the Cranial Nerves that exit from the
Jugular foramen
Glossophrayngeal (IX); Vagus (X); Accessory (XI)
