Nervous System / Special Senses

Front 1

Neuroglia

Back 1

Glial cells. Supports and protect neurons. These outnumber neurons 10:1. No nerve transmission.

Front 2

Myelinated axons

Back 2

Conduct impulses faster than un_______ axons. Form by different glial cells depending on location. Ogliodendrocytes are in the brain and spinal cord, and Schwann cells are in the peripheral nerves.

Front 3

Nodes of Ranvier

Back 3

Gaps in the myelin sheath that allow faster nerve impulse conduction due to 'skipping'.( Saltatory conduction).

Front 4

Saltatory Conduction

Back 4

Rapid means of conduction an action potential along myelinated axons. Depolarization only happens at the Nodes of Ravier.Allow vision and fine motor skills. Multiple sclerosis

Front 5

Multiple sclerosis

Back 5

Damages to myelin sheath that slows the muscle response. Muscles don't respond to what brain wants to do.

Front 6

Organization of the Nervous System

Back 6

Anatomical, Direction of impulses, and function.

Front 7

Central Nervous System

Back 7

Anatomical nervous system. Brain and spinal chord. Along the central axis of the body.

Front 8

Peripheral nervous system

Back 8

Anatomical Nervous System.Extends outward from the central axis toward the periphery of the body. Cranial nerves originate directly from the brain. Spinal nerves emerge from the spinal chord.

Front 9

Afferent Nerves

Back 9

Direction of impulses. Take impulses to the CNS. Sensory nerves .

Front 10

Efferent Nerves

Back 10

Direction of impulses. Takes impulses away from the CNS. Motor nerves to target organs. May carry fibers that are sensory, motor, or both signals.

Front 11

Somatic Nervous System

Back 11

Function. Actions under conscious, or voluntary control. Impulses sent mainly to skeletal muscle.

Front 12

Autonomic Nervous System

Back 12

Controls and coordinates involuntary functions. Ex. Slowing of the heart rate in response to an increased blood pressure. Impulses send to smooth and cardiac muscles and glands.

Front 13

Neuron Function

Back 13

Resting membrane potential. High Na outside, low inside. High K+ inside, low outside.

Front 14

Action Potential

Back 14

Nerve impulse. Depolarization and repolarization

Front 15

Depolarization

Back 15

When the neuron receives a stimulus. Na+ channels open in the membrane. Na+ flows into cell by passive diffusion. The inside of the cell becomes +.

Front 16

Repolarization

Back 16

Na+ channels close, K+ channels open as the K+ flows out of the cells. Inside of the cell is negative again, bringing it back to resting potential.

Front 17

Generation of an Action Potential

Back 17

Na+/K+ pump restores the ions on the correct side of the membrane. Outside is + and inside is -. Maintained by the pump by pumping Na+ from the inside of a neuron to the outside, and K+ from the outside to the inside. Active transport.

Front 18

Threshold Stimulus

Back 18

Stimulus that is strong enough to make the neuron response and cause completely depolarization. The all or nothing principle.

Front 19

Once an action potential in generated

Back 19

Depolarization spreads down membrane in a wave. "Nerve impulse".

Front 20

Communal nerve

Back 20

A bundle of axons

Front 21

Resting membrane potential

Back 21

Difference in electrical charge across the membrane. From differences in distribution of positive and negative ions including potassium, proteins, and other charged ions.

Front 22

Muscle cells

Back 22

modified to respond to electrical signals.

Front 23

electricity

Back 23

All communication from your body comes from ___________.

Front 24

Nervous system

Back 24

Look at slide 8

Front 25

Action potential graph

Back 25

Front 26

Threshold Stimulus and sustained threshold stimulus

Back 26

Front 27

Synaptic Transmission

Back 27

Communication between neurons. Involves the synapse, the synaptic cleft, presynaptic neuron and postsynaptic neuron.

Front 28

Synapse

Back 28

Junction between two neurons, or a neuron and a target cell.

Front 29

Synapse

Back 29

Front 30

Synaptic cleft

Back 30

Gap between adjacent neurons

Front 31

Presynaptic neuron

Back 31

Brings the depolarization wave to the synapse, and releases the neurotransmitter

Front 32

Postsynaptic neuron

Back 32

Contains receptors for the neurotransmitter.

Front 33

Step 1 in the Neurotransmitter Action

Back 33

Neurotransmitter molecules are synthesized from precursors under the influence of enzymes .

Front 34

Step 2 in the Neurotransmitter Action

Back 34

Neurotransmitter molecules are stored in vesicles

Front 35

Step 3 in the Neurotransmitter Action

Back 35

Neurotransmitter molecules that leak from vesicles are destroyed by enzymes

Front 36

Step 4 in the Neurotransmitter Action

Back 36

Action potential causes vesicles to fuse with the presynaptic membrane and release their neurotransmitter molecules into the synapse.

Front 37

Step 5 in the Neurotransmitter Action

Back 37

Released neurotransmitter molecules bind with autoreceptors and inhibit subsequent neurotransmitter release .

Front 38

Step 6 in the Neurotransmitter Action

Back 38

Released neurotransmitter molecule bind to postsynaptic receptors.

Front 39

Step 7 in the Neurotransmitter Action

Back 39

Released neurotransmitter molecules are deactivated either by reuptake or enzymatic degradation.

Front 40

Acetylcholinesterase

Back 40

Mono-amine oxidase (MAO). Antidepressants prevent breakdown and reabsorption of neurons. Degrades the synaptic transmitters. Either excitatory or inhibitory on target cell, depending on the location. Main transmitter for the parasympathetic nervous system. Neurotransmitter.

Front 41

Examples of acetylcholinesterase

Back 41

Excite motor neurons, inhibits heart rate.

Front 42

Catecholamines

Back 42

Excitatory neurotransmitter. Norepinephrine and Epinephrine (basically the same). Produced in top concave portion of the kidneys. Made in the adrenal gland in the sympathetic nervous system.

Front 43

Dopamine

Back 43

Type of neurotransmitter that is involved with automatic functions and muscle control. Found in the brain. Associate with tremors in Parkinson's disease .

Front 44

Parkinson's Disease

Back 44

Causes tremors. Lack of dopamine neuron function.

Front 45

Gamma-aminobutyric acid (GABA)

Back 45

Type of inhibitory neurotransmitter in the brain.

Front 46

Glycine

Back 46

Type of inhibitory neurotransmitter in the spinal cord

Front 47

Valium

Back 47

Type of glycine tranquilizer that works by increasing GABA effects on brain. Tranquilization leads to sedation.

Front 48

Central Nervous System

Back 48

Consist of the spinal and cord and brain, which includes the cerebrum, cerebellum, diencephalon, and the brain stem.

Front 49

Cerebrum

Back 49

Part of the brain responsible for higher order behaviors including learning, intelligence, and awareness. Consists of gyri and sulci, longitudinal fissure, gray matter, and white matter. Telecephalon.

Front 50

Cerebrum

Back 50

Folded to allow more surface area to allow more neurons, to allow more synapses, to allow more neural ability

Front 51

Frontal lobe

Back 51

Lobe of the cerebrum where voluntary movement planned, psychomotor skills, motor cortex.

Front 52

Parietal lobe

Back 52

Location of pain, touch, temperature, and perception in the cerebrum. Mostly sensory information.

Front 53

Parietal ; frontal

Back 53

________ lobe senses pain in the hand, then sends signals to the _______ lobe that figures out what needs to be done to remove pain from the hand.

Front 54

Occipital lobe

Back 54

Visual interpretation in the cerebrum

Front 55

Temporal lobe

Back 55

Auditory, behavior, and memory in the cerebrum

Front 56

Cerebellum

Back 56

Located caudal to the cerebrum. The area of the brain responsible for coordinated movement, balance, posture, and complex reflexes

Front 57

Hypoplastic Cerebellum

Back 57

Motor coordination that is not formed correctly. Subject wobbles when they move.

Front 58

Diencephalon

Back 58

Passageway between the brain and the cerebrum. Includes the hypothalamus, thalamus, and the pituitary

Front 59

Thalamus

Back 59

Regulates sensory inputs to the cerebrum (bouncer)

Front 60

Hypothalamus

Back 60

Interface between the nervous system and the endocrine system.

Front 61

Pituitary

Back 61

Endocrine, the master gland. Rests in the pituitary fossa. Produces hormones that produces the body's ciruclation. Growth hormones, water intake, etc.

Front 62

Brain stem

Back 62

Connection between the rest of the brain and the spinal cord. The most primitive part of the brain. Include the medulla oblongata (caudal part), pons, and midbrain. Basic support functions of the body including heart beat, respiration, etc. Many cranial nerve originate here.

Front 63

Brain stem

Back 63

Front 64

Meninges

Back 64

Connective tissue layer that surrounds the brain and spinal cord. Composed of three layers: dura mater, arachnoid, and pia mater.

Front 65

Gray matter

Back 65

Part of the cerebrum located in the cerebral cortex, which is the outer layer of the brain that consists of neuron cell bodies.

Front 66

White matter

Back 66

Communication in the cerebrum, how all the signals travel from the neurons to all the places they have to go. Have myelinated axons and the corpus callosum

Front 67

Myelinated axons

Back 67

Fibers beneath the cortex in white matter.

Front 68

Corpus callosum

Back 68

Fibers that connect the two halves of the cerebral cortex and allow communication in white matter.

Front 69

Midbrain

Back 69

Controls basic autonomic functions in the brain stem.

Front 70

Outline of skull layers

Back 70

Front 71

Cerebrospinal Fluid

Back 71

Circulates around the brain (subarachnoid space), within ventricle system, and within the spinal canal. Clear, colorless, and has low protein. Made by the choroid plexus in 4th ventricle.

Front 72

Functions of the cerebrospinal fluid

Back 72

Protection and buoyancy, circulate nutrients, and removes waste products.

Front 73

Blood Brain Barrier

Back 73

Separates body's blood supply in the brain from the nervous tissue. Capillary walls that have no fenestrations. Prevent many drugs, proteins, ions, and other molecules from readily passing from the blood into the brain.

Front 74

Capillary walls in the brain

Back 74

Consists of endothelial cells connected by tight junctions. Covered process of glial cells.

Front 75

Most capillaries in the body

Back 75

Front 76

Brain capillaries

Back 76

Front 77

12

Back 77

___ Nerve pairs in the brain originate directly from the brain. Each may carry sensory signals, motor signals, or both.

Front 78

Cortex

Back 78

The outer part of the spinal cord that consists of white matter (axons).

Front 79

Medulla

Back 79

Inner part of the spinal cord (gray matter). Includes the central canal which contains CSF. Middle portion where the neurons are.

Front 80

Dorsal nerve roots

Back 80

Contain incoming sensory (afferent) fibers. Emerges between each pair of adjacent vertebrae.

Front 81

Ventral nerve roots

Back 81

Contain motor (efferent) fibers. Emerges between each pair of adjacent vertebrae.

Front 82

Ganglion

Back 82

Collection of neurons .

Front 83

Somatic reflexes

Back 83

Reflex that involves the contraction of skeletal muscles

Front 84

Autonomic reflexes

Back 84

Reflexes that regulate smooth muscle, cardiac muscle, and endocrine glands.

Front 85

Contralateral reflex

Back 85

Reflex that starts on one side of the body and travels to the opposite side.

Front 86

Ipsilateral reflex

Back 86

Reflex where the stimulus and response are on the same side of the nody.

Front 87

Relfex arc

Back 87

A basic process that all reflexes have. see slide 29.

Front 88

Stretch reflex

Back 88

includes a monosynaptic reflex arc, and sensory receptor is a muscle spindle, which when stretched, sends a signal causing the muscle to contract. Example is the patellar reflex. Antagonist muscle gets signaled to relax. Slide 31.

Front 89

Monosynaptic reflex arc

Back 89

Part of the stretch reflex. Involves a sensory neuron and a motor neuron. No interneurons involved.

Front 90

Crossed Extensor Reflex

Back 90

Contralateral reflex. Afferent sensory neuron synapses with interneurons that transmit information to the opposite side of the spinal cord. Causes contraction of opposite extensor muscles. Both sides of the body.

Front 91

Crossed extensor reflex

Back 91

When you step on a nail and raise your foot, the unaffected leg bears the weight.

Front 92

Hearing

Back 92

Converts vibration of air molecules into nerve impulses are that interpreted by the brain as sound.

Front 93

temporal

Back 93

Ear structures are mostly located in the

________ bone.

Front 94

External ear

Back 94

Part of the ear that is a funnel to collect sound wave vibrations and direct them into the rest of the ear. Have the pinna and auditory canal. Made of elastic cartilage.

Front 95

Middle ear

Back 95

Part of the ear that amplifies and transmits the vibrations to the inner ear. Has the tympanic membrane and auditory ossicles.

Front 96

Inner ear

Back 96

Contains the sensory receptors that convert the mechanical vibrations to nerve impulses. Also has receptors for equilibrium part of the inner ear.

Front 97

Cochlea

Back 97

Sensory receptor in the inner ear that converts the mechanical vibrations to nerve impulses. Cochlear duct. Involves the endolymph and sensory hair cells including "Organ of Corti" and Cochlear Nerve. Surrounded by Perilymph (U-shaped tube)

Front 98

Sensory hair cell

Back 98

Sit on the basilar membrane and tops the tectorial membrane in the cochlea.

Front 99

Step 1 in sound transmission

Back 99

Sound waves are collected by the pinna, and are funneled into the auditory canal.

Front 100

Step 2 in sound transmission

Back 100

Sound waves vibrate the tympanic membrane, which vibrates the three auditory ossicles attached to membrane. Ossicles vibrate the oval window at the entrance of the cochlea.

Front 101

Step 3 in sound transmission

Back 101

Vibration of the oval window vibrates the fluid in the cochlea. Sensory hairs moved up and down by fluid wave, and tips of hair hit tectorial membrane and get bent.

Front 102

Step 4 in sound transmission

Back 102

Bending of the hairs causes cochlear nerve to send a nerve impulse (auditory signal) to the brain.

Front 103

Equilibrium

Back 103

Maintains balance by keeping track of the position and movements of the head. Involves ________ receptors, information from the eyes, and proprioceptors throughout the body. has receptors in the vestibule and semicircular canals.

Front 104

Vestibule

Back 104

Part of the inner ear involved in equilibrium that has receptors with linear motion and static head position. Have the untricle and saccule. Has gelatin with otoliths on top of sensory hairs.

Front 105

Untricle and saccule

Back 105

Patches of sensory hair in each area of the vestibule.

Front 106

Semicircular canals

Back 106

Part of the inner ear involved in equilibrium that has receptors. Has rotational movement. Has 3 fluid tubs arranged in the X, Y, and Z axis. Has the ampulla, but doesn't have otoliths.

Front 107

Ampulla

Back 107

Sensory hair structure in each area of the semicircular canals.

Front 108

Nerve supply

Back 108

Vestibulocochlear nerve.

Front 109

Eye

Back 109

Various structures to control and focus light onto sensory photoreceptors. They convert electromagnetic energy into nerve impulses. Has the optic nerve.

Front 110

externally ; internally

Back 110

Both eyelids lined by haired skin ___________ and mucous membrane ____________

Front 111

Superior palpebra

Back 111

More mobile of the eyelids and has cilia.

Front 112

Palabrae

Back 112

Superior palpebra, medial commisure, palpebral fissure, inferior palpebra, lateral commisure.

Front 113

Lacrimal glands

Back 113

Makes and secretes tears, and washes the surface of the eye. Drains into the nasolacrimal duct (nasal passage).

Front 114

Nictating membrane

Back 114

Cartilage plate. Lies medial between palpebrae and globe (eyeball). Has lymph modules and accessory lacrimal gland.

Front 115

External fibrous coat

Back 115

Layer of the globe (eyeball) including the cornea and sclera. Most superficial layer that completely surrounds the globe. Dense c.t.

Front 116

Middle vascular coat

Back 116

Uvea, layer of the globe (eyeball) including the iris, choroid, and ciliary body. Provides nourishment to the globe, controls pupillary diameter, and controls the shape of the lens.

Front 117

Internal coat

Back 117

Nervous tunic. Layer of the globe (eyeball) that includes the retina, and the nerves and vessels associated with it.

Front 118

Limbus

Back 118

Corneroscleral junction in the external fibrous coat.

Front 119

Cornea

Back 119

Takes up 1/4 of the anterior portion of the external fibrous coat. Transparent and avascular.

Front 120

Sclera

Back 120

Takes up 3/4 of the posterior portion of the external fibrous coat. Opaque and has elastic fibers.

Front 121

Iris

Back 121

Have two layers of smooth muscle, the circular (constrict) and radial (dilate), in the middle vascular coat of the eye. Located between the cornea and lens, controls pupil size, and pupil shape varies with species.

Front 122

Types of pupils

Back 122

Front 123

Granulae iridicae of equine pupillary margin

Back 123

Front 124

Horses and goats

Back 124

Horizontal shaped pupils

Front 125

Ciliary body

Back 125

Part of the middle vascular coat with muscle bundles covered by epithelium (ciliary processes). Ciliary muscles control lens shape: contract (rounder) and relax (flattens)

Front 126

Parts of middle vascular coat

Back 126

Front 127

Choroid

Back 127

Middle vascular coat that contains melanin and the tapetum lucidum

Front 128

Choroid

Back 128

Front 129

Tapetum lucidum

Back 129

Superior to the optic disc. Not in humans or pigs.

Front 130

Retina

Back 130

Part of the internal coat. Contains the photoreceptors and the optic disc. Multiple layers of neutral cells (photoreceptor cells).

Front 131

Optic disc

Back 131

Blind spots; where axons from the retina leave the eye. Retinal vessels enter and leave here.

Front 132

Photoreceptors

Back 132

Bipolar cells and ganglion cells process the information from the _______________ .

Front 133

Rods

Back 133

Photorecepting cell that are low, light gray.

Front 134

Cones

Back 134

Bright-light, color. No fovea centralis in domestic animals.

Front 135

Sensory retina

Back 135

Front 136

Neurons

Back 136

Basic function unit of the nervous system with a high requirement for oxygen. cannot reproduce but generate the cell process if the body remains intact. Have neuroglia. Has a cell body (soma or perikaryon) and dendrites (receive stimuli). Have axons and a high metabolic rate.

Front 137

Axon

Back 137

Conducts nerve impulses away. Single long process that may extend several feet. Some are myelinated. Have nodes of Ranvier.

Front 138

Anterior chamber

Back 138

Anterior portion of the chambers of the globe. Cornea to iris. 1.

Front 139

Posterior chamber

Back 139

Anterior portion of the chambers of the globe. Iris to lens. 2.

Front 140

Posterior position

Back 140

Vitreous chamber (body).

Front 141

Cornea, aqueous humor, lens, virtuous humor

Back 141

Light strikes the eye and gets refracted by ______, ___________________, ____ , _________________.

Front 142

Cornea; lens

Back 142

The ______ does most of the refraction, while the ______ only fine tunes the focus.

Front 143

When light converges onto the retina

Back 143

Photoreceptors stimulated. Nerve signal sent to brain via optic nerve. "Image" is actually sent upside down. Occipital lobe does initial processing.