A & P Exam 3 Flashcards Preview

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Flashcards in A & P Exam 3 Deck (314):
1

Microscopic nerve cells or nerve fibers are also called

neurons

2

Where are neurons found?

Brain, spinal cord, peripheral nerves

3

What is the basic functional unit of the nervous system?

Neurons

4

Neurons have a high requirement for what?

oxygen

5

What do neurons use for energy?

Glucose

6

Neurons cannot reproduce but can regenerate cell processed if the cell ____ remains intact

body

7

These cells structurally and functionally support and protect the neurons.

Neuroglia or glial cells

8

There are __X as many glial cells as there are neurons.

10X

9

Are glial cells directly involved in the transmission of information or impulses through the nervous system?

No

10

The central cell body of a neuron is also called (2 names)

soma or perikaryon

11

This nerve cell process receives stimuli from other neurons and conducts the stimuli to the cell body. Short, numerous, multi-branched projections extending from the cell body.

Dendrites

12

This nerve cell process conducts nerve impulses away from the cell body toward another neuron or an effector cell. They are single, long processes.

Axons

13

These nerve cell processes may be modified into sensory receptors that receive stimuli such as heat, cold, touch, pressure, stretch, or other physical changes from inside or outside the body.

Dendrites

14

A cell that does something when stimulated such as a muscle or gland cell.

Effector cell

15

Axons may be covered with a fatty substance that appears white.

Myelin

16

Nervous tissue containing many myelinated axons is called

white matter

17

Nervous tissue made up largely of neuron cell bodies appears as

gray matter

18

Do myelinated axons conduct impulses faster or slower than unmyelinated ones?

Faster

19

Cell membrane of glial cells tightly wrapped around the axon is called a

myelin sheath

20

Glial cells located in the brain and spinal cord are called

oligodendrocytes

21

Glial cells in the nerves outside the brain and spinal cord are called

Schwann cells

22

Gaps between adjacent glial cells on a myelin sheath are called

Nodes of Ranvier

23

A group of axons outside the CNS

nerve

24

A group of axons inside the CNS

Tract

25

A collection of cell bodies located outside the CNS

Ganglion

26

A cell body that is outside the CNS in a ganglion

sensory neuron

27

A cell body entirely within the CNS

Interneuron

28

A cell body in the spinal cord, and axon outside the CNS is called

motor neuron

29

Cell bodies are located in the ____ (sensory) or in the _____ (motor).

Ganglion
Gray matter

30

Does a nerve contain cell bodies?

No

31

Within a nerve, each fiber (axon) is surrounded by a connective tissue sheath called an ______, which insulates it from the other neurons adjacent to it.

endoneurium

32

Groups of fibers are bound by a coarser connective tissue, called the

perineurium

33

Finally, all fascicles are bound together by a tough, fibrous connective tissue sheath called the

epineurium

34

Blood vessels and lymphatic vessels serving the fibers also travel within the

nerve

35

The brain and spinal cord make up the

Central Nervous System (CNS)

36

This nervous system consists of nerves that link the CNS with the rest of the body

Peripheral nervous system (PNS)

37

Cranial nerves originate directly from the

brain.

38

Spinal nerves emerge from the

spinal cord

39

The PNS is separated into what?

Somatic nervous system and Autonomic nervous system

40

Voluntary nervous system with input from sense organs and output to skeletal muscles is called the

Somatic nervous system

41

Involuntary nervous system with input from internal receptors and output to smooth muscles and glands is called

Autonomic nervous system

42

The autonomic nervous system is divided into

Sympathetic and Parasympathetic motor systems

43

Autonomic motor system that initiates "fight or flight" responses. Involves neurotransmitter noradrenaline, so also called Adrenergic System.

Sympathetic Motor System

44

Autonomic motor system in charge of relaxing responses. Involves neurotransmitter acetylcholine, so also called Cholinergic System.

Parasympathetic Motor system

45

The sympathetic motor system is also known as

Adrenergic System

46

The parasympathetic motor system is also known as

Cholinergic system

47

Somatic motor nerves send impulses to

skeletal muscle

48

This nervous system is in charge of functions that determine the relationship of the animal to the outside world.

Somatic

49

This nervous system is in charge of functions that relate to the internal environment of the animal.

Autonomic

50

Autonomic motor nerves send impulses to (3)

smooth muscle, cardiac muscle, and glands

51

An animal turning its head in response to its name being called is an example of autonomic or somatic?

Somatic

52

Slowing of the heart rate in response to an increased blood pressure is an example of autonomic or somatic?

Autonomic

53

These nerves, also called sensory nerves, conduct impulses toward the CNS. They conduct sensations from sensory receptors in the skin and other locations in the body to the CNS.

Afferent nerves

54

These nerves, also called motor nerves, conduct impulses away from CNS towards muscles and other organs.

Efferent nerves

55

This type of nerve causes muscle contraction and movement among other things. They also cause glands to excrete a substance.

Efferent nerves

56

Cranial and spinal nerves in the PNS and nerve tracts (bundles of axons) in the CNS may carry which type of nerve fibers?

Sensory and motor

57

Afferent nerves are also called

sensory nerves

58

Efferent nerves are also called

motor nerves

59

Perception of pain from an injection of antibiotics is controlled by

Somatic, sensory

60

Conscious movement of a forelimb is controlled by

Somatic, motor

61

Perception of the amount of acidity present in the duodenum is controlled by

Autonomic, sensory

62

Slowing of heart rate in response to an increased blood pressure is controlled by

Autonomic, sensory: sensing the increased blood pressure
Autonomic, motor: slowing the heart rate

63

Constriction of blood vessels in the skin in response to cold temps is controlled by

Somatic, sensory: sensing cold temps
Autonomic, motor: constricting the vessels

64

What are the 4 different areas of the brain?

cerebrum, cerebellum, diencephalon, brain stem

65

Largest part of the brain in domestic animals. Area responsible for higher-order behaviors (learning, intelligence, awareness). Contains corpus callosum, gray and white matter.

Cerebrum

66

Ear shaped area in the cerebrum is called the

corpus callosum

67

Cerebral cortex; outer layer of the brain made up mainly of neuron cell bodies

Gray matter

68

Made up mainly of myelinated axons; fibers beneath the cortex and corpus callosum (fibers that connect the 2 halves of the cerebral cortex).

White matter

69

Folds or hills in the cerebral hemispheres.

Gyri (gyrus)

70

Shallow grooves separating the gyri. Divides the cerebral hemispheres into lobes.

Sulci (sulcus)

71

Deep grooves separating the gyri are called

Fissures

72

Prominent fissure that divides the cerebrum into right and left cerebral hemispheres.

Longitudinal fissure

73

The 2nd largest component of the brain. Located just caudal to the cerebrum. Area of the brain responsible for coordinated movement, balance, posture, and complex reflexes.

Cerebellum

74

Feline panleukopenia due to viral infection of the dam during pregnancy can cause a undergrowth of the cerebellum called

congenital cerebellar hypoplasia

75

Passageway between brain stem and cerebrum. Contains the thalamus, hypothalamus and pineal body(*different from what book says).

Diencephalon

76

Located in the diencephalon. Acts as a relay station for regulating sensory inputs to the cerebrum

Thalamus

77

Located in the diencephalon. Interface between the nervous system and the endocrine system.

Hypothalamus

78

Located in the diencephalon. Produces serotonin derivative melatonin, a hormone that affects the modulation of wake/sleep patterns and seasonal fuctions.

Pineal body/gland

79

This structure is associated with the diencephalon. It is the endocrine "master gland" that regulates hormone production and release.

Pituitary gland

80

The connection between the rest of the brain and the spinal cord. Composed of the medulla oblongata, pons, and midbrain. Area responsible for basic support functions (heart, respiration, swallowing, vomitting). Many of the cranial nerves originate from this area of the brain.

Brain stem

81

A set of connective tissue layers that surround the brain and spinal cord. Contains blood vessels, fluid, and fat. Supply nutrients and O2 to the superficial tissues of the brain and spinal cord. Provides some cushioning and distribution of nutrients of the CNS.

Meninges

82

What are the 3 tissue layers of the meninges?

Dura mater, arachnoid, pia mater

83

The tough, fibrous outer tissue layer of the meninges, just deep to the skull bone.

Dura mater

84

The delicate, spiderweb-like tissue layer of the meninges, deep to the subdural space.

Arachnoid

85

The very thin tissue layer of the meninges that lies directly on the surface of the brain and spinal cord. Deep to the subarachnoid space.

Pia mater

86

Fluid between layers of the meninges (subarachnoid space) and in ventricles (inside the brain) and the central canal (of spinal cord). Provides cushioning fuctions, regulation of autonomic functions such as respiration and vomiting, diagnostic tool.

Cerebrospinal fluid (CSF)

87

Where is CSF located (3)?

Subarachnoid space, ventricles (brain), and central canal (spinal cord)

88

What is the procedure called when collecting CSF from subarachnoid space between the atlanto-occipital joint or L5-L6?

CSF tap

89

Contrast injected into the subarachnoid space at L5-L6 is called

myelogram

90

A local anesthetic injected in the epidural space is called

epidural

91

Space between the dura mater and surrounding bone is called

epidural space

92

There is no epidural space in the skull because the dura mater is fused with the

periosteum

93

The restriction of large molecules to the vascular space is the result of tight junctions between neighboring capillary endothelial cells in the brain. This is called the

blood-brain barrier

94

This prevents many drugs, proteins, ions, and other large molecules from readily passing from the blood into the brain.

blood-brain barrier

95

This type of junction, located in the capillaries of the blood-brain barrier are not found in capillaries elsewhere in the body.

Tight junctions

96

In addition to tight junctions, the blood-brain barrier also contains processes of ____ cells that surround the outside of capillary endothelial cells.

glial

97

A protein found on endothelial cells impedes transport of various drugs from the capillaries to the brain. Approximately 35% of collies have a genetic mutation creating a non-functional protein here. This allows for ivermectin doses that would normally be blocked from the CNS to gain access to it. What is this condition called?

Ivermectin toxicity

98

How many cranial nerve pairs originate directly from the brain stem?

12 (numbered in Roman numerals)

99

What are the 2 cranial nerves that do not originate from the brain stem?

Olfactory and optic

100

Each cranial nerve may contain axons of motor neurons, axons of sensory neurons, or

combinations of both

101

The outer portion of the spinal cord that consists of white matter and surrounds the gray matter.

Cortex

102

The central part of the spinal cord composed of gray matter.

Medulla

103

This structure of the spinal cord contains the residual embryonic neural tube.

Central canal

104

The dorsal nerve roots contain ____ fibers.

sensory

105

The ventral nerve roots contain ___ fibers.

motor

106

The dorsal and ventral nerve roots emerge from the spinal cord between each pair of adjacent

vertebrae

107

Neurons in gray matter of the spinal cord that forward sensory nerve impulses to brain or other parts of the spinal cord.

Dorsal horns

108

Neurons in gray matter of the spinal cord that forward motor (efferent) nerve impulses to the spinal nerves

Ventral horns

109

When a neuron is not being stimulated, it is in a

resting state.

110

Difference in electrical charge across a neuronal membrane. The inside of the neuron is more negatively charged than the outside.

Resting membrane potential

111

Neuron receives external stimulus. Sodium channel opens on neuron cell membrane. Sodium ions flow into cell by passive diffusion. These are steps associated with

depolarization

112

Sodium channels close; K+ channels open; K+ diffuses out of the cell; the net negative charge in the cell is restored; K+ channels close. These are steps associated with

repolarization

113

The Na+ & K+ ions are now on opposite sides from where they began. Sodium-potassium pumps moves sodium & potassium ions back to their original sides. Resting state restored. These are steps associated with

repolarization

114

Specialized molecule that helps maintain cell resting state. It is an antiport since it pumps ions in different directions.

Sodium-potassium pump

115

The Na+-K+ pump pumps how many Na+ ions from inside the neuron to the outside?

3

116

The Na+-K+ pump pumps how many K+ ions from outside the neuron to the inside?

2

117

The stimulus must be sufficient to make the neuron respond and cause complete depolarization. This is known as the

threshold stimulus.

118

The neuron depolarizes to its maximum strength or not at all. This principle is known as the

all or nothing principle

119

The initial stimulus causes a spreading wave of opening sodium channels to travel along the cell membrane of the entire neuron. This is called the wave of depolarization, conduction of action potential, or

nerve impulse

120

Time period during which a neuron is insensitive to additional stimuli is called the

refractory period.

121

What are the 2 refractory periods?

Absolute and relative

122

The refractory period during sodium influx and early potassium outflow. Cell is still in depolarization/early repolarization. The cell cannot respond to stimuli.

Absolute refractory period

123

The refractory period during end of the repolarization period. It may be possible to stimulate another depolarization if stimulus is very large.

Relative refractory period

124

Myelin sheath prevents Na+ ions from flowing across the neuronal cell membrane. Depolarization wave in myelinated axons skips from 1 node of Ranvier to the next. Rapid means of conducting an action potential. This is called the

Saltatory conduction

125

Immune system destroys the myelin covering axons resulting in delayed transmission nerve impulses known as

Multiple Sclerosis

126

What happens when the depolarization wave has been successfully conducted to the end of the axon?

Neuron must release neurotransmitters to stimulate the next neuron or cell.

127

The perpetuation of nerve impulse from one neuron to the next cell is called

synaptic transmission

128

The junction between 2 neurons or a neuron and a target cell is called a

synapse

129

The gap between 2 adjacent neurons

synaptic cleft

130

The neuron bringing the depolarization wave to the synapse and releasing the neurotransmitter is called the

presynaptic neuron

131

The neuron that contains receptors for the neurotransmitter being released is called the

postsynaptic neuron

132

The branched structure on the presynaptic neuron that contain vesicles and have a terminal button.

Telodendron

133

The slightly enlarged bulb on the end of each telodendron. Also called the synaptic end bulb or synaptic knob.

Terminal button

134

The neurotransmitter is contained in _____ in the knob of the presynaptic neuron.

vesicles

135

When _______ _____ reaches the synaptic knob, vesicles fuse with the knob's cellular membrane and dump neurotransmitter into the synaptic cleft.

depolarization wave

136

______ on the postsynaptic membrane bind to the neurotransmitter. They are very specific about which neurotransmitters they will bind.

receptors

137

What are the 2 types of neurotransmitters?

Inhibitory and excitatory

138

This type of neurotransmitter usually causes an influx of sodium so that the postsynaptic membrane moves toward the threshold.

Excitatory

139

This type of neurotransmitter may cause Cl- channels or K+ channels to open up on the postsynaptic membrane. They will make the charge within the postsynaptic cell even more negative which moves it farther away from the threshold.

Inhibitory

140

This neurotransmitter can be either excitatory or inhibitory depending on its location in the body. It is excitatory to skeletal muscle cells and has an inhibitory effect on the heart rate.

Acetylcholine (Ach)

141

Acetylcholine binds to what receptors?

Cholinergic

142

Muscarinic and nicotinic are types of ____ receptors.

cholinergic

143

Norepinephrine, epinephrine, and dopamine are what type of neurotransmitter?

Catecholamines

144

Norepinephrine is associated with the _____ nervous system.

sympathetic

145

Epinephrine plays a role in the "fight or flight" reactions of the ____ nervous system. It is primarily released from the adrenal medulla.

sympathetic

146

Dopamine is involved with ____ functions and muscle control. It is mostly inhibitory.

autonomic

147

Vassopressor is a type of _____ that constricts blood vessels causing increased blood pressure.

dopamine

148

Catecholamines bind to what receptors?

adrenergic

149

What are the 3 types of adrenergic receptors?

Alpha 1, beta 1, beta 2

150

A type of inhibitory neurotransmitter found in the brain. It cannot be manipulated by drugs.

GABA (gamma-aminobutyric acid)

151

A type of inhibitory neurotransmitter found in the spinal cord. It cannot be manipulated by drugs.

glycine

152

What would happen if the neurotransmitter were allowed to remain in the synapse or on the postsynaptic receptor?

The postsynaptic neuron would continue to be excited or inhibited.

153

The enzyme found on the postsynaptic membrane that breaks down acetylcholine.

Acetylcholinesterase

154

Organophosphates in ____. Parasympathetic nervous system is overstimulated. SLUDD

Acetylcholinesterase

155

Monoamine oxidase (MAO) & catechol-o-methyl transferase (COMT) break down which neurotransmitter?

norepinephrine

156

MAOI's act as ______. Allows norepi to prolong its excitatory effect on the brain.

anti-depressants.

157

This nervous system controls automatic functions at the subconscious level. It differentiates into sympathetic and parasympathetic.

Autonomic

158

For the sympathetic nervous system, nerves emerge from which parts of the CNS?

thoracic and lumbar vertebral regions (thoracolumbar system)

159

For the parasympathetic nervous system, nerves emerge from which parts of the CNS?

brain and sacral vertebral regions (cranial-sacral)

160

Efferent motor nerves of sym & parasym nervous systems are composed of a sequence of at least ___ neurons to conduct an impulse from the spinal cord or brain to a muscle or gland.

2

161

What are the 2 neurons of the efferent motor nerves called?

Preganglion neuron
Postganglion neuron

162

This efferent neuron has its cell body in the brain or spinal cord and the axon extends out from the CNS to an autonomic ganglion.

preganglionic

163

A cluster of neuronal cell bodies outside the CNS

Ganglion

164

A series of autonomic ganglia outside the thoracolumbar area of the spinal cord.

sympathetic ganglion chain

165

Sympathetic ______ neuron synapses w/either a neuron in the ganglion chain or a neuron beyond the sympathetic ganglion chain.

preganglion

166

Which preganglionic neuron travels directly from the brain and sacral region of the spinal cord to its target organ?

Parasympathetic

167

Which system has a long preganglionic neuron and a short postganglionic neuron?

Parasympathetic

168

Which system has a short preganglionic neuron and a long postganglionic neuron?

Sympathetic

169

What is the primary neurotransmitter of the sympathetic nervous system?

Norepinephrine

170

Neurons that release norepinephrine are what kind of neurons?

Adrenergic neurons

171

Alpha 1, and adrenergic receptor, cause vasoconstriction of what?

Skin, GI tract, & kidneys

172

Beta 1, and adrenergic receptor, increases what?

heart rate & force of contraction

173

Beta 2, and adrenergic receptor, causes what?

bronchodilation

174

Beta blockers are used for

high blood pressure

175

The primary neurotransmitter of the parasympathetic nervous system is

acetylcholine

176

Neurons that release Ach are

cholinergic neurons

177

Anticholinergic drugs, such as ____, bind to cholinergic receptors blocking Ach from binding.

atropine

178

Both sympathetic and parasympathetic preganglionic neurons release

Ach.

179

This type of Ach receptor is found on postganglionic neurons of sympathetic & parasympathetic systems & between motor neurons and muscles.

Nicotinic

180

This type of Ach receptor is found on target organs and tissues supplied by the postganglionic neuron of the parasympathetic nervous system.

Muscarinic

181

Disease in which autoantibodies specific for Ach receptors block and/or damage receptors. Csx: generalized muscle weakness, megaesophagus. Diagnosis: reversal of signs following test dose of anticholinesterase drugs.

Myasthenia gravis

182

Anticholinesterase drugs prevent the breakdown of

Ach

183

Which nervous system does this describe?
preganglionic neuron> ach> nicotinic receptor on postganglionic neuron> norepi> adrenergic receptor (a1, b1, b2) on tissue

Sympathetic

184

Which nervous system does this describe?
preganglionic neuron> ach> nicotinic receptor on postganglionic neuron> ach> muscarinic receptor on tissue

Parasympathetic

185

Rapid, automatic responses to stimuli in the internal or external environment designed to protect body and maintain homeostasis.

Reflexes

186

Reflex happens ____ and an impulse will be sent to the brain as long as there isn't a lesion interrupting it on the way to the brain.

locally

187

All reflexes have the same basic structure call the

reflex arc

188

This receptor receives a stimulus, reaches threshold, and sends the nerve impulse along the sensory neuron to the gray matter of the spinal cord or brain stem.

Sensory receptor

189

Where does the sensory neuron travel to get to the spinal cord and what part of the spinal cord does it go to for the reflex arc.

dorsal nerve root, dorsal horn

190

These neurons serve to integrate incoming sensory impulse with other impulses from other sensory neurons. They are located in the CNS.

Interneurons

191

This neuron sends an impulse to the target organ (muscle or gland).

Motor neuron

192

What part of the spinal cord is the motor neuron located in and where does it leave the spinal cord for the reflex arc.

ventral horn, ventral nerve root

193

This type of reflex involves contraction of skeletal muscles.

Somatic

194

This type of reflex regulates smooth muscle, cardiac muscle and endocrine glands.

Autonomic

195

This type of reflex starts on one side of the body and travels to the opposite side.

Contralateral

196

This type of reflex, the stimulus and response are on the same side of the body.

Ipsilateral

197

This type of reflex arc is the simplest. It involves a sensory neuron & a motor neuron with only 1 synapse between them without any interneurons.

Monosynaptic reflex arc

198

This type of reflex is also known as the flexor reflex. It involves several interneuron synapses and results in contraction or flexing of muscles.

Withdrawal reflex

199

This type of reflex is a contralateral reflex. If withdrawal reflex is initiated, afferent sensory neuron synapse with interneurons and causes contraction of opposite extensor muscles.

Crossed extensor reflex

200

With injury, intact reflex arcs caudal to the spinal cord trauma become

hyperreflexive

201

Trauma where reflex arc enters or leaves the spinal cord, or damage to the sensory nerve or motor nerve of the reflex, results in either _____ or absent reflex arcs.

hyporeflexive

202

Light tap on the medial canthus of the eye produces a blink of the eyelids.

Palpebral reflex

203

Normal response to shining light in the eye of an animal is for the iris in both eyes to constrict.

Pupillary light reflex (PLR)

204

Touch, hearing and balance are what types of stimuli?

Mechanical

205

Hot and cold are what types of stimuli?

thermal

206

Vision is what type of stimuli

electromagnetic

207

Taste & smell are what type of stimuli?

Chemical

208

How many senses are there?

10

209

This type of sense if distributed generally throughout the body. It includes visceral, touch, temperature, pain, proprioception.

General senses

210

This type of sense if organized into specific, often complex sensory organs & structures all located in the head. It includes taste, smell, hearing, equilibrium, vision.

Special senses

211

Hunger, thirst, hollow-organ fullness are part of what sense? Also includes stretch receptors in GI tract & urinary bladder. If wall of organ is stretched, it is very painful with the exception of the urinary bladder. Organs can be handled, cut or crushed without any apparent pain.

Visceral sensations

212

Body position and movement are part of what sense?

Proprioception

213

Pain involves what type(s) of stimulus?

Mechanical, chemical or thermal

214

Visceral sensations involve what type(s) of stimulus?

chemical and mechanical

215

Sensation of something being in contact with the surface of the body. Also known as tactile sense.

Touch

216

Sensation of something pressing on the body surface.

Pressure

217

Temperature receptors in the skin; detect upward and downward changes in skin temperature.

Superficial temperature receptors

218

Temperature receptors in the hypothalamus; monitor the temperature of the blood

Central temperature receptors

219

Pain receptors are called

nociceptors

220

The process of experiencing pain

Nociception

221

Pain receptors are widely distributed inside & on the surface of the body but are not present in one organ.

Brain

222

What are the 4 processes of nociception?

transduction, transmission, modulation, perception

223

The conversion of stimulus into nerve impulse. Part of nociception.

transduction

224

The conduction of nerve impulse to the spinal cord. Part of nociception.

Transmission

225

Changing of the sensory nerve impulses can occur in the spinal cord & significantly influence the information the brain receives. Can amplify or suppress sensory impulses.

Modulation

226

Awareness of painful stimuli. Conscious perception occurs in the cerebral cortex as well as other areas of the brain.

Perception

227

Prevention of modulation during surger?

Give pre-analgesics & local anesthetics

228

Stretch receptors for this sense are located in skeletal muscles, tendons, ligaments & joint capsules. Receptors keep the CNS informed about the movements of limbs, positions of joints, the state of contraction of muscles, and the amount of tension being exerted on tendons & ligaments.

Proprioception

229

Taste is also known as

gustatory sense

230

What is the stimulus for the gustatory sense?

chemical

231

Chemical receptors for taste are located in taste buds on the sides of ____. They are also found in the lining of the mouth and _____.

papillae
pharynx

232

Taste buds are tiny, round structures made up of ____ cells.

Gustatory

233

Tiny openings on the surface of each taste bud that allow dissolved substances to enter the taste buds & contact the sensory receptors.

Taste pores

234

What is the stimulus of olfactory sense?

Chemical

234

What cranial nerves are involved in taste?

CN VII: facial, both sensory & motor
CN IX: glossopharyngeal, both sensory & motor

235

Where is the olfactory region located?

High in nasal passages

236

Olfactory epithelium is made up of what 2 types of cells?

Sensory (olfactory) cells and supporting cells

237

What projects up from the olfactory cells into the icons layer that covers the epithelium?

Hairlike processes (modified dendrites)

238

Odor molecules dissolve in the ....... And contact the sensory processes.

Mucus

239

What cranial nerve is involved in the olfactory sense?

CN I: olfactory, sensory

240

Hearing is also know as what?

Auditory

241

What type of stimulus is involved in hearing?

Mechanical

242

Hearing converts ...... Of air molecules into nerve impulses.

Vibrations

243

What cranial nerve is involved in hearing?

CN VIII: vestibulocochlear, sensory

244

This part of the ear acts as a funnel to collect sound wave vibrations and direct them to the eardrum.

External ear

245

This part of the ear amplifies and transmits the vibrations from the eardrum to the inner ear

Middle ear

246

This part of the ear contains the sensory receptors that convert the mechanical vibrations to nerve impulses, along with receptors for the equilibrium sense.

Inner ear

247

This structure of the external ear is made of elastic cartilage and skin.

Pinna

248

This structure of the external ear is usually an L shaped membrane lined tube. It includes a vertical and horizontal section.

External ear (auditory) canal

249

This structure, also known as the eardrum, is in the external ear.

Tympanic membrane

250

Sound wave vibrations strike the tympanic membrane and cause it to

Vibrate

251

The middle ear is located in what part of the skull?

Tympanic bulla

252

The middle ear is filled with air and contains the ossicles and the opening of the

Eustachian tube

253

These 3 small bones in the middle ear link the tympanic membrane with the cochlea of the inner ear. They act as a system of levers that transmit sound wave vibrations from the tympanic membrane to the cochlea. What is the name for all 3 bones?

Ossicles

254

The outermost ossicle, attached to the tympanic membrane. Also called the hammer.

Malleus

255

The middle ossicle, also called the anvil.

Incus

256

The medial most ossicle, attached to the membrane that covers the oval window of the cochlea. Also called the stirrup.

Stapes

257

This connects the middle ear cavity with the pharynx. It equalized air reassure on the two sides of the tympanic membrane. Swallowing or yawning causes the slit like opening of this to stretch open allowing are to enter or leave to equalize pressure.

Eustachian tube

258

The procedure that allows access to the middle ear. Fluid can then be removed from the middle ear.

Myringotomy

259

What structures are in the inner ear?

Cochlea, vestibule, semicircular canals

260

The hearing portion of the ear is located in the

Cochlea

261

A snail shell-shaped spiral cavity in the inner ear

Cochlea

262

The receptor organ of hearing is the

Organ of corti

263

The long tube in the cochlea that contains the organ of corti and is filled with endolymph.

Cochlear duct

264

The cochlear duct is filled with fluid called

Endolymph

265

A U-shaped tube containing another fluid, ......., lies on either side of the cochlear duct.

Perilymph

266

These windows are membrane-covered openings at the ends of the U-shaped tube in the inner ear.

Round window and oval window

267

The Organ of Corti consists of these hearing receptors, supporting cells, and tectorial membrane.

Hair cells

268

What are the receptor cells of hearing? They have tiny, hairlike projections (modified dendrites) on their surfaces.

Hair cells

269

The gelatin-like tectorial membrane lies ..... Of the hair cells. (Above or below)

Above

270

Sound wave vibrations cause the ....... ...... and ossicles in the middle ear to vibrate

Tympanic membrane

271

As the stapes vibrates back and forth, it pushes and pulls the membrane covering the

Oval window

272

The vibration of the oval window causes the ...... around the cochlear duct to vibrate.

Perilymph

273

The membrane of the ..... ........ acts as a pressure relief.

Round window

274

Fluid vibration causes the cochlear duct to move which causes the tectorial membrane and the hair cells of the ...... ... ...... To rub against each other. This generates nerve impulses that travel to the brain and are interpreted as sound.

Organ of Corti

275

Equilibrium has what type of stimulus?

Mechanical

276

This sense helps maintain balance by keeping track of the position and movements of the head

Equilibrium

277

Equilibrium involves receptors and info from the ..... And ......

Eyes and proprioceptors

278

Receptors for equilibrium are located where in the inner ear?

Vestibule and semicircular canals

279

This structure of the inner ear is located between the cochlea and semicircular canals. It is composed of 2 saclike spaces that are continuous with the cochlear duct and filled with the same endolymph and surrounded by perilymph.

Vestibule

280

What are the 2 saclike spaces in the vestibule?

Utricle and saccule

281

In each utricle and saccule is a patch of sensory epithelium called the

Macula

282

In the macula are crystals of calcium carbonate called

Otoliths

283

What causes otoliths and the gelatinous matrix to put pressure on the hairs in the vestibule?

gravity

284

The movement of the head bends the sensory hairs. This generates nerve impulses that give the brain information about the ______ of the head.

position

285

This structure related to equilibrium is located opposite the vestibule from the cochlea.

Semicircular canals

286

Three semicircular canals oriented in different planes at ___ angles to each other.

right

287

Endolymph-filled membranous tubes of the semicircular canals are surrounded by

perilymph

288

The enlarged area near the utricle end of each semicircular canal is called an

ampulla

289

The receptor within the ampulla of the semicircular canals. Similar to the macula of the vestibule. Supporting cells and hair cells with modified dendrites sticking up into the cupula.

Crista ampullaris

290

The gelatinous structure that functions as a float that moves with the endolymph in the semicircular canals.

Cupula

291

When the head moves, endolymph movement in the semicircular canals lags behind the movement of the canal itself. This generates impulses that give the brain information about ____ of the head.

motion

292

Photoreceptors that detect the image and generate visual nerve impulses are in a single layer of cells in the

retina

293

What cranial nerves are involved in vision?

CN II: optic, sensory
CN III: oculomotor, motor

294

What are the 3 layers of the eyeball?

outer fibrous layer
middle vascular layer
inner nervous layer

295

This part of the eye is transparent and admits light to the interior of the eye. It is richly supplied with pain receptors. Arrangement of collagen fibers, no blood vessels.

Cornea

296

Corneal edema or corneal dehydration causes the cornea to become

opaque

297

This is the "white" of the eye made of dense fibrous connective tissue.

Sclera

298

The junction of the cornea and the sclera

Limbus

299

This area of the eye, also called the middle vascular layer, contains the choroid, iris & ciliary body.

Uvea

300

This area of the eye is between the sclera and retina. It contains pigment and the blood vessels that supply the retina. In most animals, (except people & swine) it forms the tapetum lucidum.

Choroid

301

The highly reflective area in the rear of the eye. It acts as an amplifier to aid low-light vision.

Tapetum

302

After light has passed through the photoreceptors, it reflects off the _____ and passes back through the photoreceptors again, stimulating them a second time.

Tapetum

303

This part of the middle vascular layer of the eye is the pigmented muscular diaphragm. It controls the amount of light that enters the posterior part of the eyeball.

Iris

304

The opening at center of iris

pupil

305

The muscle fibers of the iris that are arranged ____ (radially or circularly) enlarge the pupil when the contract.

radially

306

The muscle fibers of the iris that are arranged ____ (radially or circularly) constrict the pupil when the contract.

circularly

307

The condition when the pupils of an animal are different sizes.

Anisocoria

308

The ring-shaped structure behind the iris. Contains tiny muscles that adjust shape of the lens to allow near & far vision.

Ciliary body

309

The muscles contained within the ciliary processes attached to the lens by the

suspensory ligaments

310

This structure of the inner nervous layer of the eye lines the back of the eye and contains the sensory receptors for vision, the rods & cones

retina

311

This compartment of the eye is in front of the lens. It contains a clear watery fluid. It is subdivided into anterior & posterior chambers.

Aqueous compartment

312

The clear, watery fluid in the aqueous compartment

aqueous humor

313

The aqueous humor is produced by the cells of the ___ ____, and drained by the ___ _ _____ and returned to the bloodstream.

Ciliary body
canal of Schlemm