Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PHGY 209 > CNS/Sensory > Flashcards

CNS/Sensory Flashcards

1
Q

What are spinal nerves responsible for?

A

Somatic sensation:
Touch
Temperature
Pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the afferent system?

A

Sensory input, cell bodies out of CNS (axons out of CNS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Efferent

A

Motor output

Cell bodies in CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the cranial nerves?

A

Somatic, visual, olfactory, taste, auditory, vestibular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where do cranial nerves project to?

A

Brainstem or other parts of the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the motor output of the CNS called

A

Efferent (motor output)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Spinal Nerves functions

A

Somatic sensation
- touch

  • temperature
  • pain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are somatic efferent nerves?

A

Innervate skeletal muscle, only excitatory, motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are autonomic efferent part of nervous system do?

A

Innervates interneurons, smooth and cardiac muscle, excitatory and inhibitory (enteric nervous system)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the white matter in the spinal cord?

A

Axons running up and down the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the purpose of the central canal?

A

Allow CSF to flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where are the cell bodies of the efferent neurons found?

A

In the gray matter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where are the cell bodies of the neurons whose axons carry afferent signals into spinal cord?

A

In the dorsal root, more specifically dorsal root ganglion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How many cranial nerves are there?

A

12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How many cranial nerves enter or leave the brain stem?

A

10 (pairs, one per side) of 12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the only two nerves that do not enter or leave the brain stem called?

A

Olfactory and optic nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Steps of Nervous System development

A
  1. Fertilized egg (ovum)
  2. Ball of cells
  3. Blastocyst (week 1)
  4. Blastocyst (week 2)
  5. Blastocyst (week 3)
  6. Week 3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Week 1 Blastocyst develops

A

inner cell mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Week 3 Blastocyst develops

A

embryonic disk

neural plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the three layers that make up the embryonic disk, and their location.

A

Ectoderm (outermost layer)
Mesoderm (middle)
Endoderm (inner)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Neural groove

A

a shallow median groove of the neural plate between the neural folds of an embryo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What develops in week 4 of the neural tube

A

vesicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Neural Crest becomes part of

A

PNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Neural tube becomes

A

CNS and part of PNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Neural Tube is composed of

A

Forebrain, Midbrain, Hindbrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Forebrain becomes

A

Cerebal hemispheres and Thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Midbrain becomes

A

Midbrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Hindbrain becomes

A

Cerebellum, pons, medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Rest of Neural tube becomes

A

Spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Cavity becomes

A

the ventricles and central canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What do ventricles contain (+amount)

A

150 ml of cerebral spinal fluid (CSF)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Where is CSF produced, and how much per day?

A

Produced in the choroid plexus (in the four ventricles, but mainly the two laterals), 500 ml/day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Describe the general composition of CSF?

A

Sterile, colorless, acellular fluid that contains glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Cerebrospinal spinal fluid function

A

1) Supports and cushions the CNS. Specific gravity of CSF and the brain are equal.
2) Provides nourishment to the brain.

3) Removes metabolic waste through
absorption at the arachnoid villi.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How is CSF circulated?

A

Passively , not pumped

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Where does CSF enter?

A

The subarachnoid space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Hydrocephalus

A

an abnormal buildup of fluid in the ventricles (cavities) deep within the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Communicating Hydrocephalus

A

The flow of CSF is blocked after it exits the ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Noncommunicating Hydrocephalus

A

The flow of (CSF) is blocked along one or more of the narrow passages connecting the ventricles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Meninges cover the ____ and _____ ____

A

brain and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What are the 3 meninges (membrane) of the CNS?

A

Dura mater, Arachnoid membrane, Pia mater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Where does CSF return to the blood?

A

at the dural sinus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What substrate is metabolized by the brain?

A

Usually only glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

T/F: There is a lot of glycogen in the brain

A

F: Very little glycogen in the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What does the brain need continuous supply of? (2)

A

glucose and oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Glucose transport into the brain does not require ____

A

insulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

A few seconds of blood supply interruption can lead to

A

loss of consciousness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

A few minutes of blood supply interruption can lead to

A

neuronal death (stroke)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What % of blood in circulation does the brain receive?

A

15%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Brain is __% of total mass

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is the use of the circle of willis?

A

SAFETY FACTOR - Able to ensure there is constant supply of blood to brain by ensuring that if one side is compromised, there is necessary blood flow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

CSF moves from

______ to _____ through _____ to _____ through _____ to _____ to _____ back to _____

A

Heart
Chorioid plexus

ventricles
subarachnoid space
archnoid villi
dural sinus
venous system
Heart
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Blood moves from
______ to either _____ arteries or _____ arteries.

The _____ arteries moves straight to _____ whereas the ______ arteries moves through _____ to _____. Then to the _____ to the ______ system back to _____

A

Heart
vertebral arteries

carotid arteries
carotid arteries
circle of willis
vertebral arteries
basilar artery
circle of willis
brain
venous system
heart
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Blood-brain barrier

A

capillary wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Function of astrocytes (glia) (4)

A
  1. provide strucutral support
  2. induce tight juctions
  3. glutamate K+
  4. phagocytosis of debris
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Sensation

A

Awareness of sensory stimulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Perception

A

The understanding of a sensation’s meaning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

T/F: We perceive energy of a sensory stimulus directly

A

F: We do not perceive the “energy” of a sensory stimulus directly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

T/F: We only perceive the neural activity that is produced by sensory stimulation.

A

T: We only perceive the neural activity that is produced by sensory stimulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

How do tight junctions impact the effects of the capillary wall of endothelial cells?

A

It heavily controls diffusion of things across capillary wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What properties do drugs need to be able to move from blood to extracellular space?

A

Lipid-soluble or hitch a ride with active transport mechanism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What is the law of specific nerve energies?

A

Regardless of how a sensory receptor is activated, the sensation felt corresponds to that of which the receptor is specialized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What is the law of projection?

A

Regardless of where in the brain you stimulate a sensory pathway, the sensation is always felt at the sensory receptor location

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

(Law of specific nerve energies/projection):

Rub your eyes hard and you will see light.

A

Law of specific nerve energies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Penfield electrically stimulated somatic sensory cortex and patients perceived somatic sensation in the body

A

Law of projection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

(Law of specific nerve energies/projection): Phantom limb pain after amputation.

A

Law of projection:

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What is the labeled line principle?

A

The brain knows the modality and location of every sensory afferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

6 sensory systems:

A

Visual, Auditory, Vestibular, Somatosensory, Gustatory, Olfactory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Modality of Vestibular

A

Balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Modality of Somatosensory

A

Somatic Senses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

4 Somatic Senses

A

Touch
Pain

Proprioception
Thermal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Taste stimulates

A

Sweet
Sour

Salt
Bitter
Umani

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Stimulus Energy of Somatosensory system

A

Mechnical, thermal, chemical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Stimulus Energy of Vestibular sensory system

A

Gravity, Acceleration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What is transduction?

A

Transduction in the nervous system typically refers to stimulus-alerting events wherein a physical stimulus is converted into an action potential, which is transmitted along axons towards the central nervous system for integration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What is responsible for the different afferent responses to constant stimulation?

A

Because of adaptation where non changing stimulus does not lead to constant stimulus (ie putting clothes on in the morning and not feeling them after a while)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Stimulus Energy of Gustatory sensory system

A

Chemical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Stimulus Energy of Olfactory sensory system

A

Chemical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Receptor class of Visual sensory system

A

Photorecptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

Receptor class of Auditory sensory system

A

Mechanoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

Receptor class of Vestibular sensory system

A

Mechanoreceptors

82
Q

Receptor class of Somatosensory system

A

Mechanoreceptors
Chemoreceptors

Thermoreceptors
Nociceptors

83
Q

Receptor class of Gustatory sensory system

A

Chemoreceptors

84
Q

Receptor class of Olfactory sensory system

A

Chemoreceptors

85
Q

Which of sensory systems use photoreceptors?

A

Visual

86
Q

Which of sensory systems use mechanoreceptors?

A

Auditory
Vestibular

Somatosensory

87
Q

Which of sensory systems use chemoreceptors?

A

Somatosensory
Gustatory

Olfactory

88
Q

Which of sensory systems use thermoreceptors?

A

Somatosensory

89
Q

Which of sensory systems use nociceptors?

A

Somatosensory

90
Q

Modaility

A

General class of a stimulus

91
Q

Steps of sensory receptors (5)

A
  1. Stimulus energy
  2. receptor membrane
  3. transduction
  4. ion channel activation
  5. afferent
92
Q

For stimulus energy there must be

A

adequate stimulus (specificity)

93
Q

Stimulus energy is converted into

A

afferent activiity

94
Q

Steps of stimulus energy being converted into afferent activity (5)

A
  1. Stimulus energy
  2. receptor potential
  3. action potentials
  4. propagation of action potentials
  5. release of neurotransmitters
95
Q

What are the types of afferent response adaptations?

A

Non-adapting (encodes stimulus intensity and slow changes)

slowly adapting (some stimulus intensity and moderate stimulus changes)

rapidly adapting (fast stimulus changes)

96
Q

Magnitude of receptor potential

A

determines the frequency with which action potentials are generated

97
Q

Afferent adaption allows us to be

A

sensitive to changes in sensory input

98
Q

Receptive field

A

The region in space that activates a sensory receptor or neuron
stimuilus location

99
Q

Overlapping RFs produce a

A

population code

100
Q

Acuity

A

ability to differentiate one stimulus from another

101
Q

High/Low acuity location: Lips

A

High

102
Q

High/Low acuity location: Back

A

Low

103
Q

High/Low acuity location: Hands

A

High

104
Q

Small RF means ____ acuity

A

High

105
Q

Large RF means ____ acuity

A

Low

106
Q

What is the purpose of lateral inhibition?

A

It sharpens sensory acuity

Enhances the profile of activity of the efferent, and we are able to tell more accurately where the input is coming from

107
Q

Lateral Inhibition

A
  • Sharpens sensory acuity

- Process by which stimulated neurons inhibit the activity of nearby neurons by interneurons

108
Q

2nd order neurons

A

carry signals from the spinal cord to the thalamus

109
Q

Interneurons

A

Found only in CNS

It also connects to other interneurons, allowing them to communicate with one another.

110
Q

What do top-down, or descending pathways do?

A

They modulate sensory inputs and can actually inhibit sensory input

111
Q

Sensory information is shaped by both

A

“bottom up” and “top down” mechanisms

112
Q

Touch

A

Mechanoreceptors with specialized end organs that surround the nerve terminal. These end organs allow only selective mechanical information to activate the nerve terminal.

113
Q

What are Meissner’s Corpuscles?

A

Fluid-filled structure enclosing the nerve terminal (tip of finger, ex). They are rapidly adapting -> light stroking and fluttering

114
Q

What is the Merkel disk?

A

Small epithelial cells surround the nerve terminal. They are slowly adapting -> pressure and texture

115
Q

Superficial layers receptors:

A

Merkel disk, Meissner’s corpuscle

116
Q

What are pacinian corpuscles?

A

Deep layer structure, Large concentric capsule of connective tissue surround the nerve terminal -> rapidly adapting, strong vibrations

117
Q

Deep layers receptors:

A

Pacinian corpuscle, Ruffini endings

118
Q

What are Ruffini endings?

A

Deep layer, nerve endings wrap around a spindle-like structure, slowly adapting -> stretch and bending of the skin (shape of object)

119
Q

How are mechanoreceptors activated?

A

Stretching the cytoskeletal strands

120
Q

Proprioception

A

Muscle spindles provide sense of static position and movement of limbs and body.

121
Q

Describe thermoreceptors?

A

Free nerve endings containing ion channels that respond to difference temperature ranges
They do not have specialized nerve ending like mechanoreceptors

122
Q

What can activate cold afferents, without actual cold?

A

Menthol

123
Q

What can activate a warm afferent, without heat?

A

capsaicin and ethanol

124
Q

Extreme temperatures activate

A

pain receptors

125
Q

What are the receptors responsible for pain?

A

Nociceptors, free nerve ending containing ion channels that open in response to intense mechanical deformation, excessive temperature, or chemicals.

126
Q

How are nociceptors activated?

A

Response to intense mechanical deformation, excessive temperature or chemicals

127
Q

What is special about pain afferents?

A

They are highly modulated (enhanced or suppressed)

128
Q

What are visceral pain receptors and what are they activated by?

A

Nociceptors on internal environments, such as organs, and are activated by inflammation

129
Q

Describe the pathway of nociceptors used to signal pain to the brain?

A

Stimulus occurs, nociceptors become activated and the signal travels up the nociceptive afferent, which fires APs, reaches the spinal cord and release Substance P (neurotransmitter), which activates second order neurons that carries information up to brain

130
Q

How are nociceptors modulated and enhanced?

A

Enhancement of surrounding nociceptors by injured tissue and afferent feedback onto mast cells -> dilation of nearby blood vessels -> pain the next day signals to you to avoid use of injured part

131
Q

Nociceptors are enhanced by many

A

mediators

132
Q

What is the enhancement of nociceptors following an injury called?

A

Hyperalgesia

133
Q

Describe the pathway a signal takes from the tip of finger to brain?

A

Afferent of mechanoreceptors (cell bodies found in dorsal root ganglion) extend their axon towards the spinal cord, enter through dorsal root, and move to dorsal column (which carries axons up and down), towards the brain stem (medulla)

134
Q

What is ipsilateral and contralateral?

A

Same side and opposite side

135
Q

Touch and Proprioception route

A

Dorsal Root ganglion
Dorsal columns

Medulla
Medial lemniscus
Thalmus
Somatosensory cortex

136
Q

Dorsal columns (senses)

A

Touch and Proprioception

137
Q

(Contralateral or Ipsilateral) Touch and proprioception

A

Ipsilateral

138
Q

(Contralateral or Ipsilateral) Temperature and Pain

A

Contralateral

139
Q

Temperature and Pain route

A

Dorsal Root ganglion
Dorsa, horn

Anterolateral column
Branches into the reticular formation
Thalamus
Somatosensory cortex

140
Q

Commonly synapse on the same neurons in the spinal cord

A

Visceral & somatic pain afferents

141
Q

Heart attacks commonly produce pain

A

in the left arm

142
Q

What is referred pain?

A

Referred pain is pain perceived at a location other than the site of the painful stimulus/ origin. It is the result of a network of interconnecting sensory nerves, that supplies many different tissues

143
Q

Analgesia

A

Reduction of pain through presynaptic inhibition

144
Q

Opiate neurotransmitters

A

Presynaptic inhibition

Stop substance P from being released in spinal cord

145
Q

How do descending pathways reduce pain?

A

Through presynaptic inhibition. Descending pathways from brainstem release opiate neurotransmitters (presynaptic inhibition) which blocks the release of substance P in spinal cord -> pain is not perceived

146
Q

What does morphine do?

A

Binds to presynaptic opiate receptors and block release of substance P

147
Q

Visual perception is dependent on

A

context

148
Q

What is a Brown-Sequard Lesion?

A

Brown-Sequard syndrome (BSS) is a rare neurological condition characterized by a lesion in the spinal cord which results in weakness or paralysis (hemiparaplegia) on one side of the body and a loss of sensation (hemianesthesia) on the opposite side

149
Q

Lens (purpose)

A

refracts (bends) light to a single point

150
Q

Light is refracted by

A

the cornea and lens

151
Q

What refracts more light: Cornea or lens

A

Cornea

152
Q

What accommodates near vision?

A

The lens accommodates for changes in object location,

conformation changes of lens are controlled by ciliary muscles

153
Q

What is meant when we say the eye is myopic and what structural difference is responsible?

A

Nearsightedness, eyeball is too long

154
Q

What is meant when we say the eye is hyperopic and what structural difference is responsible?

A

Farsighted, eyeball too short

155
Q

Nearsightedness is corrected by a ____ lens

A

concave

156
Q

Farsightedness is corrected by a ____ lens

A

convex

157
Q

Cataract

A

changes in lens colour (more opaque)

158
Q

What is presbyopia?

A

The lens gets stiff and unable to accommodate for near vision

159
Q

What is astigmatism?

A

The lens or the cornea is misshapen, cornea is not spherical

160
Q

Fovea centralis

A

the retinal circuitry is shifted out of the way

161
Q

What is visual transduction?

A

Visual phototransduction is the sensory transduction of the visual system. It is a process by which light is converted into electrical signals in the rod cells, cone cells and photosensitive ganglion cells of the retina of the eye

162
Q

Bipolar cells

A

only neurons that connect the outer retina to the inner retina

163
Q

Horizontal cells

A

Help integrate and regulate the input from multiple photoreceptor cells

164
Q

Amacrine cells

A

the major carriers of rod signals to the ganglion cells in the retina

165
Q

Ganglion cells

A

Make up the optic nerve

166
Q

Rods/Cones:

High sensitivity, night vision

A

Rods

167
Q

Rods/Cones:

Low sensitivity, day vision

A

Cones

168
Q

Rods/Cones:

More rhodopsin, captures more light

A

Rods

169
Q

Rods/Cones:

High amplification, single photon closes many Na+ channels

A

Rods

170
Q

Rods/Cones:

Slow response time

A

Rods

171
Q

Rods/Cones:

Faster response time

A

Cones

172
Q

Rods/Cones:

Lower amplification

A

Cones

173
Q

What is found binded to rhodopsin?

A

Chromophore

174
Q

Rods/Cones:

Less opsin

A

Cones

175
Q

Rods/Cones:

More sensitivity to scattered light

A

Rodes

176
Q

Rods/Cones:

Most sensitive to direct axial rays

A

Cones

177
Q

Rods/Cones system:

Low acuity: not present in central fovea, highly convergent

A

Rod System

178
Q

Rods/Cones system:

High acuity: concentrated in fovea, less convergent

A

Cone system

179
Q

Rod/Cone system:

Achromatic: one type opsin

A

Rod System

180
Q

Rods/Cones system:

Chromatic: three types of opsin

A

Cone system

181
Q

When bright light goes to dark

A

Temporary blindness until rods “re-activate” and take over

182
Q

What activates the opsin molecule and what happens?

A

Light (photons) activate the opsin molecule, and as it is activated, the opsin and chromophore separate

183
Q

When dark goes to bright light

A

Rods are initially saturated. Temporary blindness until

rods “inactivate” and cones take over

184
Q

T/F: It takes time to put the chromophore and opsin back together

A

T

185
Q

Retina reports relative/absolute intensity of light

A

relative

186
Q

Retinal ganglion cells

A

signal the relative differences of the light (contrast) across their receptive fields
- B/W

  • Colour
187
Q

Photoreceptors are sensitive to ________

A

wavelength

188
Q

The opsin molecule determines

A

the chromatic sensitivity of the photoreceptor

189
Q

The output of the retina encodes

A

relative values of brightness and colour

190
Q

What activates the G-protein cascade, and what does the cascade do?

A

The separated opsin activates the g-protein cascade, which convert cGMP to GMP

191
Q

What happens when there is no more cGMP in the cell?

A

Na+ channels close

192
Q

What does light cause in the photoreceptors?

A

Hyperpolarize

193
Q

Optic tract

A

both eyes with contralateral visual field

194
Q

Optic nerve

A

one eye with both visual fields

195
Q

What do retinal ganglion cells do?

A

Retinal ganglion cells signal the relative difference of the light (contrast) across the receptive fields

196
Q

Cervical Nerves
- body part

  • pairs
A

Neck, shoulders, arms and hands

8

197
Q

Thoracic Nerves
- body part

  • pairs
A

Shoulders, chest, upper abdominal wall

12

198
Q

What happens at the optic Chiasm?

A

The axons of the retinal ganglion cells that are closest to nose (nasal half) cross

The axons of the retinal ganglion cells from the peripheral halves do not cross

199
Q

Lumbar Nerves
- body part

  • pairs
A

Lower abdominal wall, hips, and legs

5

200
Q

Sacral Nerves
- body part

  • pairs
A

Genitals and lower digestive tract

5

PHGY 209 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions