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Flashcards in Nervous System Deck (217):
1

collect info from other neurons

dendrites

2

contains the nucleus and most cell organelles

cell body

3

integrates info collected by dendrites and initiates nerve impulses at the beginning of the axon

axon hillock

4

conducts action potential away from the cell body

axon

5

nerve cells that are excitable = generate and transmit electrical signals, more specifically action potentials

neurons

6

modulate neuron activity (provide support)

glia

7

at the tip of the axon that carries Ap away from presynaptic cell to postsynaptic cell

axon terminals

8

originating cell body

presynaptic cell

9

receiving target cell

postsynaptic cell

10

cluster of nerve cells

ganglion (ganglia)

11

ganglia may be enlarged and fused at the anterior end to form a --

brain

12

cnidarians have simple networks of neurons called -- that achieves little or no integration of information

nerve nets

13

in bilaterally symmetric animals, the ganglia are often --

paired

14

The increase in brain size in humans is mostly due to an increase in the --

cerebral cortex

15

the human brain is also highly -- and more of it is devoted to associative functions

convoluted

16

In -- body size and brain size are correlated, but higher primates fall above this regression line

vertebrates

17

In humans, the -- is the largest brain area and is made even larger by convolutions

cerebral cortex

18

The anterior end of neural tube develops into --

hindbrain, midbrain, and forebrain

19

most "primitive" part of the brain that controls breathing and circulation and helps regulate behavior patterns

hindbrain

20

processes visual and auditory info (eg reflexive response to noise)

midbrain

21

most complex and developed portion of the brain

forebrain

22

the posterior end of neural tube develops into

spinal cord

23

the hindbrain becomes

medulla, pons, and cerebellum

24

controls physiological functions such as breathing

medulla and pons

25

coordinates muscle activity and maintaining balance

cerebellum

26

Brainstem is composed of

midbrain, medulla, and pons

27

all info traveling between the spinal cord and higher brain areas must pass through the --

brainstem

28

consists of the diencephalon and telencephalon

forebrain

29

Forebrain -- = thalamus and hypothalamus

diencephalon

30

two cerebral hemispheres (also called cerebrum) that process sensory perception, learning, memory and conscious behavior

telencephalon

31

T or F: CNS is encased in bone

True

32

T or F: PNS is encased in bone

False

33

lobe for visual

Occipital

34

lobe for complex sensory processing (visual and auditory)

Temporal

35

lobe for representation of the body and movement in space

Parietal

36

lobe for motor cortex and involved in planning

Frontal

37

The cortex is folded into ridge -- and valleys -- giving it bigger surface area

gyri, sulci

38

The two hemispheres are -- with respect to all functions

not symmetrical

39

divides the frontal and parietal lobes

central sulcus

40

located in front of the central sulcus and controls muscles in specific body areas

primary motor cortex

41

parts of the body with fine motor control (face and hands) have -- representation

disproportionate

42

inability to identify objects

agnosias

43

If the left brain hemisphere is damaged, there is often some form of -- which is a deficit in the ability to use or understand words

aphasia

44

In frontal lobe, just in front of primary motor cortex essential for speech but if damaged can still read and understand language

Broca's area

45

in temporal lobe, damage results in inability to speak sensibly (written or spoken language is not understood) but can still produce speech

Wernicke's area

46

near Wernicke's area; essential for integrating spoken and written language

Angular gyrus

47

the inability to recognize faces even though you can identify people based on hearing or touching

prosopagnosia

48

the left and right hemispheres are connected by white matter called

corpus callosum

49

In the PNS, bundles of axons are called

nerves

50

In the CNS, bundles of axons are called

tracts

51

There are a -- of neuron forms

variety

52

The -- of all neurons can generate and conduct action potentials

plasma membranes

53

The axon terminals comes extremely close to the membrane of the target cell forming a --

synapse

54

evolution of nervous systems: network of neurons -->

ganglia --> brain-spinal cord

55

sensory relay station

thalamus

56

a vital part of the endocrine system which regulates physiological functions and drives

hypothalamus

57

bundles of axons are surrounded by -- tissue

connective

58

some axons in a nerve may be carrying info to the CNS while others in the same nerve are carrying info from the CNS to --

the body's organs

59

The cerebrum is about 3-4 mm and officially has -- layers but is essentially a -- sheet

6, 2D

60

verbal and logic

LEFT

61

visual and spatial

RIGHT

62

behavior/movement

FRONT

63

sensory input/perception

BACK

64

more complex

OUTSIDE

65

more essential

INSIDE

66

right body

LEFT

67

left body

RIGHT

68

divides the frontal and parietal lobes

central sulcus

69

located in the front of the central sulcus that controls muscles in specific body areas

primary motor cortex

70

parts of the body with fine motor control, such as face and hands, have

disproportionate representation

71

just behind the central sulcus that receives touch and pressure info from the thalamus

primary somatosensory motor cortex (parietal lobe)

72

areas with high densities of mechanoreceptors have

disproportionate representation

73

Normal language ability depends on the flow of info among areas of the -- cerebrum

left

74

Damage to the -- causes contralateral neglect syndrome where a person is unable to recognize stimuli from the left side of the body

right parietal lobe

75

If the -- is cut, knowledge or experience of the right hemisphere can no longer be expressed in language

corpus callosum

76

-- allow the AP to pass directly between two neurons

electrical synapses

77

In vertebrates, most synapses are --

chemical

78

chemical AP can travel up at speeds up to

100 m/sec

79

grow around axon and insulate axon with myelin (not in brain or spinal cord)

Schwann cells

80

1. induce tight junctions between endothelial cells
2. establish lining of capillaries
3. establish blood brain barrier

Astrocytes

81

myelin sheaths in brain and spinal cord

oligodendrocytes

82

act as macrophages and mediators of inflammatory responses

microglia

83

-- is an autoimmune disease that affect myelin

Multiple sclerosis

84

-- typically prevents antibodies form entering the brain and spinal cord

blood-brain barrier

85

The sodium-potassium pump requires energy to move -- and establish concentration gradients

Na + out and K+ in

86

The inside of the cell is usually -- relative to the outside because "leak channels" allow some ions (K+) to diffuse out

negative

87

the electrical charge difference across the membrane which is measured in millivolts between the inside and outside of a neuron

membrane potential

88

the steady state membrane potential of a neuron

resting potential (-60mV)

89

Under resting conditions:

K permeability is high (many open K channels)
Na permeability is low (Na channels are closed)
Cl permeability is also low

90

membrane potential becomes more positive

depolarization

91

membrane potential becomes more negative

hyperpolarization

92

An -- is a sudden, rapid reversal in the voltage across a portion of the plasma membrane

action potential

93

For -- positively charged ions flow into the cell making the inside of the cell more positive than the outside

1 or 2 milliseconds

94

open and close in response to the membrane's potential

voltage-gated channels

95

open and close in response to the presence or absence of a specific chemical/NT which can bind directly to the channel protein

chemically-gated channels

96

only K+ channel open

resting potential

97

voltage-gated Na+ channel open

depolarized: Na+ ions enter the cell traveling down its concentration gradient

98

chemically gated K+ channel open

hyperpolarized

99

The membrane potential at any given time depends on

how many and which channels are open

100

the resting potential is -- because the resting membrane is permeable mainly to K+

negative

101

Until a -- is reached when large numbers of these channels simultaneously open and a very rapid AP "spike" is produced

threshold

102

A new AP cannot be generated again at the part of the membrane until the voltage-gated Na -- itself for the next AP

resets

103

there is a short -- during which theses voltage-gated Na channels cannot open

refractory period

104

begins slowly through already open K channels

repolarization: more K ions leave the cell traveling down its concentration gradient

105

T or F: AP are conducted down axons without reduction in signal

True

106

An AP is -- because it spreads to adjacent membrane regions

self-generating

107

-- enables saltatory conduction

myelin

108

The -- are regularly spaced gaps in the myelin along an axon

nodes of Ranvier

109

Saltatory Conduction: AP are generated at the -- and the positive current flows down the inside of the axon

nodes

110

AP appear to jump from node to node, a form of propagation called

saltatory conduction

111

Myelin is oil-like and reduces the "capacitance" of the axon membrane, with fewer ions needed to depolarize

change in membrane potential is faster and requires less energy

112

are chemical synapses between motor neurons and skeletal muscles

neuromuscular junctions

113

the neurotransmitter of neuromuscular junctions is

acetylchloline

114

The arrival of -- causes the release of a neurotransmitter

AP

115

the ability to sense stimuli arising within the body regarding position, motion, and equilibrium

proprioception

116

Membrane receptor proteins of sensory cells generally cause ion channels to open or close, causing a change in membrane potential called

receptor potential

117

the receptor protein itself is part of the ion channel and by changing its conformation, opens and closes the channel pore

ionotropic sensory detection

118

the receptor protein is linked to a G protein that activates a cascade of intracellular events that eventually open or close ion channels

metabotropic sensory detection

119

ion channels or directly affect ion channels

ionotropic receptor proteins

120

examples of ionotropic receptor proteins

mechanoreceptors, thermoreceptors, electrosensors

121

affect ion channels through G proteins and second messengers

metabotropic receptor proteins

122

examples of metabotropic receptor proteins

chemoreceptors, photoreceptors

123

different senses connect to different targets

labeled lines

124

responsible for taste and smell
also monitor internal environment such as CO2 blood levels

chemoreceptors

125

sense of smell

olfaction

126

sense of taste

gustation

127

olfactory sensors are embedded in -- at the top of the nasal cavity (vertebrates)

epithelial tissue

128

axons extend to the -- in the brain, dendrites end in olfactory hairs on the --

olfactory bulb, nasal epithelium

129

a molecule that enters the nasal cavity and binds to an olfactory receptor protein on the cilia of olfactory receptor neurons (ORNs)

odorant

130

olfactory receptor proteins are specific for particular --

odorants

131

In the olfactory bulb, axons from ORNs with the same receptor types cluster together to form -- which integrate info from olfactory receptors

glomeruli

132

an accessory structure that traps odorant molecules, converting 3D diffusion to 2D diffusion

mucus

133

a paired tubular structure embedded in the nasal epithelium with chemoreceptors in the walls (found in amphibians, reptiles, and many mammals)

Vomeronasal organ

134

chemical signals used to communicate among individuals of the same species

pheromones

135

Taste buds are replaced every -- but the associated neurons live on

few days

136

Gustation chemoreceptors don't fire action potentials instead they release transmitter modulates the firing rate of action potentials in --

2nd order sensory neurons

137

flavor is due to a combination between -- and --

taste and smell

138

Na+ channels for salty
Modulation of K+ channels by H+ for sour

ionotropic transduction

139

one or two sweet receptors and many bitter receptors via G proteins and 2nd messenger cascades

metabotropic transduction

140

are found in muscles, tendons, and ligaments

stretch receptors

141

auditory systems use -- to sense sound waves

hair cells

142

sensory cells that respond to physical (mechanical) forces

mechanoreceptors

143

adapt slowly and provide continuous info about anything touching the skin; most important tactile receptor found in hairy and nonhairy skin

Merkel's discs

144

deeper in skin, adapt slowly and provide info about vibrating stimuli of low frequencies

Ruffini's corpuscles

145

deeper in skin, adapt rapidly and provide info about vibrating stimuli of high frequencies

Pacinian's corpuscle

146

pain, itch, temperature

free nerve endings

147

(nonhairy) very sensitive but adapt rapidly and provide info about chanhges in things touching skin (roll)

Meissener's corpuscles

148

diminishing response to repeated stimulation which enables animals to ignore background conditions but remain sensitive to changing or new stimuli

adaptation

149

mechanoreceptors in muscle cells (stretch receptors)

muscle spindles

150

the -- in tendons and ligaments provides info about the force generated by contracting muscles and prevents muscle tearing

Golgi tendon organ

151

the bending of -- or hair cells one way or the other depolarizes or hyper polarizes the cell, causing the postsynaptic fiber to increase or reduce its firing rate

stereocilia

152

tells fish about movement with respect to water, about pressure waves, and neighboring fish

lateral line system

153

The lateral line system (at its hair cells) evolved into - systems

vestibular auditory and electrosensory

154

We have 3 pairs of semicircular canals that signal -- in 3 orthogonal planes: roll, pitch, yaw

rotational acceleration

155

move and bend stereocilia

ampullae

156

We have vestibular organs for -- and --

gravity and linear acceleration

157

In the base of each semicircular canal duct is a -- with a cluster of hair cell stereocilia

cupula

158

When shifting fluid pushes on the cupula, it bends the -- causes a graded potential

sterocilia

159

Hair cell depolarizes when bent one way releasing -- neurotransmitter

more

160

Hair cell hyper polarizes when bent the other way releasing -- neurotransmitter

less

161

Hair cells do not fire AP -- do

2nd order cells

162

Outer ear consist or -- and --

pinna and auditory canal

163

Middle ear consists of the -- and --

tympanic membrane and middle ear ossicles

164

serve to collect sound waves

outer ear

165

serves to amplify sound waves for impedance matching between air fluid of inner ear

middle ear

166

middle ear ossicles

malleus, incus, and stapes

167

consists of cochlea

inner ear

168

transduce sound waves to action potentials in auditory nerve

inner ear

169

a tapered and coiled chamber composed of three parallel canals separated by the vestibular membrane and the basilar membrane

cochlea

170

sits on the basilar membrane; transduces pressure waves into action potentials

organ of Corti

171

High frequency sound vibrates the -- of the basilar membrane

base

172

Low frequency sound vibrates the -- of the basilar membrane

apex

173

Upper and lower canals of the cochlea are joined at --

distal end

174

flexible membrane at the end of the tympanic canal of the cochlea

round window

175

responsible for photosensitivity

rhodopsin

176

photosensitivity depends on the ability of visual pigments to absorb -- and undergo a change in --

photons of light, conformation

177

part of rhodposin that is not photosensitive alone

opsin

178

nonprotein, light-absorbing functional group cradled at the center of opsin and covalently bound to it

11-cis-retinal

179

entire rhodopsin molecule sit withing the -- of a photoreceptor cell

plasma membrane

180

eyecups

flatworms

181

Arthropods have compound eyes consisting of many optical units called -- each with its own narrow-angle lens

ommatidia

182

vertebrate eye consists of 1 optical unit with -- lens

wide-angle

183

tough connective tissue layer that bounds the vertebrate eye

sclera

184

At the front of the eye, the sclera forms the transparent -- through which light passes to enter the eye

cornea

185

Just inside the cornea is the pigmented -- which gives eye color

iris

186

controls the amount of light that reaches photoreceptor cells at the back of the eye; under neural control

iris

187

What happens to iris and pupil in bright?

iris constricts and small pupil

188

What happens to iris and pupil in dark?

iris relaxes and large pupil

189

the central opening of the iris

pupil

190

Behind the iris is the crystalline protein -- which make fine adjustments in the focus of images falling on the retina

lens

191

photosensitive layer at the back of the eye

retina

192

cornea and fluids within the eye -- light rays passing through them so they are focused on the retina

bend

193

lenses become -- with age

less elastic

194

During embryonic development, neural tissue grows out from brain to form the --

retina

195

photoreceptor cells are always shedding discs from their -- ends as their new ones are being generated by the inner segments

distal

196

pigmented epithelial cells -- the shed discs

phagocytose

197

each outer segments is totally renewed about every --

2 weeks

198

photoreceptors of the vertebrate retina

rod cells and cone cells

199

highly light sensitive adn perceive shades of gray in dim light

rod cells

200

-- segment of rod cells contains stack of discs made up of plasma membrane densely packed with rhodopsin

outer

201

-- segment of rod cells contain cell nucleus, mitochondria, and other organelles

inner

202

Na+ continually enters the outer segment in the --

Dark

203

Stimulated by light the cell --

hyperpolarizes

204

a single photon of light results in the

closure of many Na+ channels

205

function at high light levels and are responsible for high-acuity color vision of day-active

cone cells

206

highest density of cone cells is in the area of retina that receives light from the center of the visual field, a region called the --

fovea

207

low sensitivity to light and contribute little to night vision

cone cells

208

closest layer of neurons in retina to the lights and thus light

ganglion cells

209

central layer of neurons in retina

biopolar, horizontal, and amacrine cells

210

the -- of the retina fire AP

ganglion cells

211

patch of photoreceptors that communicate with a ganglion cell forms a

circular receptive field

212

form synapses with neighboring photoreceptors and bipolar cells

horizontal cells

213

form local interactions between bipolar cells and ganglion cells

amacrine cells

214

bundle of axons in nerve carry info about many things simultaneously

nerves

215

2 unrelated stimuli become linked in same response

associative learning

216

can consciously recall and describe

declarative memory

217

memory of how to perform a task

procedural memory