ZOOL 2403 BOROS EXAM 3 TTU STUDY GUIDE
5 cranial senses - Answer -olfaction, taste, vision, hearing and equilibrium
Olfactory pathway - Answer -odor-olfactory receptors-olfactory nerves-olfactory bulbs-
olfactory tracts-olfactory cortex
Gustatory Pathway - Answer -Taste buds are on the dorsal surface of the tongue
taste-receptors- cranial nerves-medulla-gustatory cortex
6 primary taste sensations - Answer -sweet
salty
bitter
sour
umami
water
Cranial Nerves - Answer -Facial nerve(CN VII)- anterior 2/3s on tongue
Glossopharyngeal (CN IX)- posterior 1/3 on tongue
3 Layers of the eyeball - Answer -Outer layer
Middle Layer
Inner Layer
Outer Layer of the Eye - Answer -Dense connective tissue
1. The Sclera- White sheath protecting eyeball.
2. The Cornea- Transparent anterior continuation of the sclera that protects the lens.
The cornea is avascular and can be transplanted.
Middle Layer of the Eye - Answer -Loose connective tissue
1. Choroid- Contains blood vessels that supply oxygenated nutrients to the tissue of the
eye.
2. Ciliary Body- Anterior continuation of the choroid, contains smooth muscle called
ciliary muscles to control the shape of the lens for focusing on an object
3. Iris- Gives the eye color, it is composed of smooth muscle which change the size of
the pupil to regulate the amount of light entering the eye.
Inner Layer - Answer -Nervous tissue layer
1. Retina- contains photoreceptors associated with optic nerve(CN II)
Rods and Cones are here
Rods - Answer -Receptors activated by dim light
Used for night vision
Black and White vision
Used for peripheral vision
,Cones - Answer -Receipts activated by bright light
Used for daylight vision
Color Vision
Used for central vision
Posterior Cavity - Answer -Transparent Gel(99% Water)
Fills 80% of the eyeball
Helps keep the retina in place
Not produced until you are 4-5 Yrs old
Only 1/2 full by the time you're 70 Yrs old
It is not replaced.
Visual Pathways - Answer -Light-Optic Receptors-Optic Nerves- Optic Chiasm-
Thalamus-Visual Cortex
Inferior Rectus - Answer -Eye looking down- Oculomotor nerve(III)
Medial Rectus - Answer -Eye looking medially- Oculomotor nerve (III)
Superior Rectus - Answer -Eyes looking Up- Oculomotor nerve (III)
Lateral Rectus - Answer -Eye Looking laterally- abducens nerve (VI)
Inferior Oblique - Answer -Eye rolls, looking up, and laterally out-oculomotor nerve(III)
Superior Oblique - Answer -Eye rolls, looking down, and laterally out- trochlear
nerve(IV)
The 5 steps of the hearing process - Answer -1.Sound waves travel along the external
ear canal
2. Sound waves arrive at tympanic membrane
3. Vibrations of tympanic membrane causes ossicles to move
4.Movement of stapes at oval window generates pressure waves in the fluid filled
cochlea of the inner ear
5. Pressure waves in the inner ear finally travel to the round window
Cochlea - Answer -It contains 3 circular chambers that create vibrations along the floor
of the middle chamber called the basilar membrane.
Hair Cells - Answer -Bending hair cells open an ion channel in the hair cells
membranes, this causes ions to rush into hair cells, this activates hair cells, and
stimulates CN VIII
, Vestibular Apparatus - Answer -Also in the inner ear and it is connected to CN VIII,
associated with equilibrium and balance, is composed of semi-circular canals and
saccule and utricle
Semi-circular canals - Answer -Contains a structure calles a cupola filled with a
gelatinous substance, receptors called hair cells embedded on it, are simulated by head
rotation. The cells bend, opening ion channels, this activates hair cells and stimulates
CN VIII, this also helps you maintain your balance during head rotation
Saccule and Utricle - Answer -Contains recepters called hair cells stimulated by gravity
and linear acceleration/deceleration.
Hair cells are embedded in a gelatinous material containing calcium carbonate crystals
called otolith that bend hair cells when moved
Sensory Pathway - Answer -1.Originates at receptors in the periphery
2. Ascends on axons of sensory neuron in the white matter of spinal cord
3. Is relayed to cell bodies of a sensory neuron in the gray matter of cerebral
cortex(CNS), where it becomes conscious
Spinal Reflex - Answer -A motor response produced when a sensory neuron synapses
on a spinal cord motor neuron.
Its very fast and occurs before the information reaches the brain, it is also involuntary.
Two types are monosynaptic and polysynaptic
Monosynaptic - Answer -Stretch reflex, a sensory neuron synapses directly on cell
body of a spinal cord motor neuron
The stretch reflex occurs constantly to help you maintain an upright position
Step in a stretch reflex - Answer -1.A stretch stimulates muscle spindle
2. Axons in a dorsal root send info to sensory neurons in dorsal root ganglion
3. Sensory neuron synapses with motor neuron
4.Axons in a ventral root send info out from activated
Somatic Nervous System - Answer -Innervates skeletal muscles
It is a voluntary system
Initiates skeletal muscle contraction
1-neuron system
Autonomic Nervous System - Answer -Innervates smooth and cardiac muscle
Is involuntary
Coordinates smooth or cardiac muscle contraction
2-neuron system
The somatomotor system - Answer -Somatomotor neuron cell bodies are located in the
CNS
Their axons synapse directly on skeletal muscles in the periphery
5 cranial senses - Answer -olfaction, taste, vision, hearing and equilibrium
Olfactory pathway - Answer -odor-olfactory receptors-olfactory nerves-olfactory bulbs-
olfactory tracts-olfactory cortex
Gustatory Pathway - Answer -Taste buds are on the dorsal surface of the tongue
taste-receptors- cranial nerves-medulla-gustatory cortex
6 primary taste sensations - Answer -sweet
salty
bitter
sour
umami
water
Cranial Nerves - Answer -Facial nerve(CN VII)- anterior 2/3s on tongue
Glossopharyngeal (CN IX)- posterior 1/3 on tongue
3 Layers of the eyeball - Answer -Outer layer
Middle Layer
Inner Layer
Outer Layer of the Eye - Answer -Dense connective tissue
1. The Sclera- White sheath protecting eyeball.
2. The Cornea- Transparent anterior continuation of the sclera that protects the lens.
The cornea is avascular and can be transplanted.
Middle Layer of the Eye - Answer -Loose connective tissue
1. Choroid- Contains blood vessels that supply oxygenated nutrients to the tissue of the
eye.
2. Ciliary Body- Anterior continuation of the choroid, contains smooth muscle called
ciliary muscles to control the shape of the lens for focusing on an object
3. Iris- Gives the eye color, it is composed of smooth muscle which change the size of
the pupil to regulate the amount of light entering the eye.
Inner Layer - Answer -Nervous tissue layer
1. Retina- contains photoreceptors associated with optic nerve(CN II)
Rods and Cones are here
Rods - Answer -Receptors activated by dim light
Used for night vision
Black and White vision
Used for peripheral vision
,Cones - Answer -Receipts activated by bright light
Used for daylight vision
Color Vision
Used for central vision
Posterior Cavity - Answer -Transparent Gel(99% Water)
Fills 80% of the eyeball
Helps keep the retina in place
Not produced until you are 4-5 Yrs old
Only 1/2 full by the time you're 70 Yrs old
It is not replaced.
Visual Pathways - Answer -Light-Optic Receptors-Optic Nerves- Optic Chiasm-
Thalamus-Visual Cortex
Inferior Rectus - Answer -Eye looking down- Oculomotor nerve(III)
Medial Rectus - Answer -Eye looking medially- Oculomotor nerve (III)
Superior Rectus - Answer -Eyes looking Up- Oculomotor nerve (III)
Lateral Rectus - Answer -Eye Looking laterally- abducens nerve (VI)
Inferior Oblique - Answer -Eye rolls, looking up, and laterally out-oculomotor nerve(III)
Superior Oblique - Answer -Eye rolls, looking down, and laterally out- trochlear
nerve(IV)
The 5 steps of the hearing process - Answer -1.Sound waves travel along the external
ear canal
2. Sound waves arrive at tympanic membrane
3. Vibrations of tympanic membrane causes ossicles to move
4.Movement of stapes at oval window generates pressure waves in the fluid filled
cochlea of the inner ear
5. Pressure waves in the inner ear finally travel to the round window
Cochlea - Answer -It contains 3 circular chambers that create vibrations along the floor
of the middle chamber called the basilar membrane.
Hair Cells - Answer -Bending hair cells open an ion channel in the hair cells
membranes, this causes ions to rush into hair cells, this activates hair cells, and
stimulates CN VIII
, Vestibular Apparatus - Answer -Also in the inner ear and it is connected to CN VIII,
associated with equilibrium and balance, is composed of semi-circular canals and
saccule and utricle
Semi-circular canals - Answer -Contains a structure calles a cupola filled with a
gelatinous substance, receptors called hair cells embedded on it, are simulated by head
rotation. The cells bend, opening ion channels, this activates hair cells and stimulates
CN VIII, this also helps you maintain your balance during head rotation
Saccule and Utricle - Answer -Contains recepters called hair cells stimulated by gravity
and linear acceleration/deceleration.
Hair cells are embedded in a gelatinous material containing calcium carbonate crystals
called otolith that bend hair cells when moved
Sensory Pathway - Answer -1.Originates at receptors in the periphery
2. Ascends on axons of sensory neuron in the white matter of spinal cord
3. Is relayed to cell bodies of a sensory neuron in the gray matter of cerebral
cortex(CNS), where it becomes conscious
Spinal Reflex - Answer -A motor response produced when a sensory neuron synapses
on a spinal cord motor neuron.
Its very fast and occurs before the information reaches the brain, it is also involuntary.
Two types are monosynaptic and polysynaptic
Monosynaptic - Answer -Stretch reflex, a sensory neuron synapses directly on cell
body of a spinal cord motor neuron
The stretch reflex occurs constantly to help you maintain an upright position
Step in a stretch reflex - Answer -1.A stretch stimulates muscle spindle
2. Axons in a dorsal root send info to sensory neurons in dorsal root ganglion
3. Sensory neuron synapses with motor neuron
4.Axons in a ventral root send info out from activated
Somatic Nervous System - Answer -Innervates skeletal muscles
It is a voluntary system
Initiates skeletal muscle contraction
1-neuron system
Autonomic Nervous System - Answer -Innervates smooth and cardiac muscle
Is involuntary
Coordinates smooth or cardiac muscle contraction
2-neuron system
The somatomotor system - Answer -Somatomotor neuron cell bodies are located in the
CNS
Their axons synapse directly on skeletal muscles in the periphery
