Oat Biology Ch 11: Nervous System

Front 1

Nervous System

Back 1

Controls most body functions and enables organisms to receive and respond to stimuli from external and internal environment. It is composed of neurons (specialized nervous tissue) and neurological cells that support and protect the neurons

Front 2

What are the two divisions of the nervous system

Back 2

CNS

PNS

Front 3

What are neurons?

Back 3

Functional unit of nervous system and converts stimuli to electrochemical signals and conduct it throughout the body

Front 4

What are dendrites

Back 4

Cytoplasmic extensions that receive information and direct towards the cell body (soma

Front 5

What is the cell body (soma)

Back 5

Controls nucleus and metabolic activitiy of neuron

Front 6

What is the axon?

Back 6

Transfers action potential away from the cell body

Front 7

What are most axons sheathed by

Back 7

Myelin

Front 8

What is the nodes of Ranvier?

Back 8

Gaps between the myelin

Front 9

What produces myelin in the CNS

Back 9

Olugodendrocytes

Front 10

What produces myelin in the PNS

Back 10

Schwann Cells

Front 11

What do axons end in?

Back 11

Synaptic terminals

Front 12

What does the synaptic terminals do

Back 12

Neutransmitters are released into the synapse

Front 13

What are the types of cells in the CNS

Back 13

Astrocytes

Olugodendrocytes

Microglia

Ependymal Cells

Front 14

What are the cells in the PNS

Back 14

-Schwann Cells

-Satellite Cells

Front 15

What do the Astrocytes do

Back 15

-Maintain integrity of the blood-brain barrier

-Regulate nutrient and dissolved gas concentrations

-Absorb and recycle NTs

Front 16

What do the oligodendrocytes do?

Back 16

Myelinate CNS axons

-Provide structural framework for the CNS

Front 17

What do microglia do?

Back 17

Remove cellular debris and pathogens

Front 18

What do ependymal cells do?

Back 18

Line the brain ventricles

Aid in production, circulation and monitoring of CSF

Front 19

What do satellite cells do

Back 19

Surround the nuron cell bodies in the ganglia

Front 20

What do schwann cells do?

Back 20

Enclose the axons in the PNS and aid in the myelination of some peripheral axons

Front 21

What are the function of the neuron?

Back 21

Receive signal from sensory receptors or other bodily neurons and create action potentials to release NTs

Front 22

Are neurons still polarized at rest?

Back 22

Yes

Front 23

What is the typical resting potential?

Back 23

-70 mV

Front 24

Is it more negative inside or outside the cell

Back 24

Inside

Front 25

Why is the resting potential created

Back 25

Because of the soidum/Potassium pump

Front 26

What does the Na+/K+ pump transport

Back 26

3 Sodium out and 2 potassium in

Front 27

What is the selective permeability of the cell membrane for sodium and potassium

Back 27

Cell membrane more permeable to potassium

So some potassium that was pumped into the cell can diffuse out through facilitated diffusion making the inside even more negative

Front 28

How do action potentials occur

Back 28

If cell body is depolarized past the threshold potential the voltage gated ion channels will open. (Gated sodium channels open so soidum comes in and increases depolarization to the next termation. Continuting the process and moving the action potential toward the terminal.

Once the action potentail reaches the synaptic terminal, final voltage gated channel opens for calcium. Calcium rushes in and triggers the exocytosis of synaptic vessicles containing neurotransmitters

Front 29

What is the refractory period

Back 29

A period after an action potential during which new action potentials are very difficult or impossible to initiate immediately What

Front 30

What does a larger diameter do for the rate of impulse propogation

Back 30

Increases it

Front 31

What does more myelination do for the rate of impulse propogation

Back 31

Increases it

Front 32

How is NT removed from the synpase?

Back 32

*Taken up by the uptkae carrier to be recycled and degraded

*Diffused out of synapse

Front 33

What does Curare do?

Back 33

Blocks postsynaptic acetylcholine receptors (IE on muslces) so ACH can't interact so leads to muscle relaxation and paralysis

Front 34

What does botulinum toxin do?

Back 34

Prevents the release of acetylcholine form the presynaptic membrane and also results in paralysis

Front 35

What does anticholinesterases do?

Back 35

Used as nerve gases and in the insecticide parathion. As the name implies these substances inhibit the activity of the acetylcholinesterase enzyme responsible for degrading ACH released into the synapse

As a result, ACH is not degraded and continues to affect postsynaptic membrane. No coordinated muscular contraction can take place

Front 36

What are affarent neurons

Back 36

Carry sensory information from the external to the internal environment to the brain and spinal cord?

Front 37

What is the efferent neurons?

Back 37

Motor commons from the brain or spinal cord to various parts of the body (muscle or glands)

Front 38

What is the interneuron

Back 38

Local circuir between the sensory and motor neuron in brain and spinal cord

Front 39

What is a plexus

Back 39

Network of nerve fibers

Front 40

What is a ganglia

Back 40

Cluster of cell bodies in the PNS

Front 41

What is the nuclei

Back 41

Cluster of cell bodies in the CNS

Front 42

What does the central nervous system consist of

Back 42

Brain

Spinal cord

Front 43

What are the matters of the brain?

Back 43

Gray matter

White matter

Front 44

What does the gray matter of the brain contan

Back 44

*Cell bodies

*Found on the outside

Front 45

What does the white matter of the brain contain?

Back 45

*Myelinated axons

*Found on the inside of the brain

Front 46

What is the forebrain

Back 46

*Telencephalon and diencephalon

-Major componenet is the cerebral cortex

Front 47

What is the cerebral cortex

Back 47

Gray matter processes and integrates sensory input and motor responses and is important for memory and creative though

Front 48

What is the olfactory bulb found in the forebrain

Back 48

Reception andi ntegration of small

Front 49

What does the diencephalon contain

Back 49

Thalamus

Hypothalamus

Front 50

What is the thalamus

Back 50

Relay and integration center for spinal cord and cerebral cortex

Front 51

What is the hypothalamus do

Back 51

Controls visceral functions usch as hunger, thrist, sex drive, water balance, blood pressure and temperature regulation

Also plays role in the endocrine system

Front 52

What does the midbrain do

Back 52

Relay center for visual and auditory impulses

-Also helps with motor control

Front 53

What is the hindbrain

Back 53

Posterior part of the brain

Front 54

What does the hindbrain consist of

Back 54

Cerebellum

Pons

Medulla

Front 55

What does the cerebellum do

Back 55

-Modulate motor impulses initiated by the cerebral cortex and is important in maintainence of balance, hand-eye coordination, and timing of rapid movements

Front 56

What does the pons do

Back 56

Acts as a relay center to allow the cortx to communicate with the cerebellum

Front 57

What does the medulla do

Back 57

controls many vital functions such as breathing, heart rate and GI activity

Front 58

What constitutes the brainstem

Back 58

Midbrain

Pons

Medulla

Front 59

What is the spinal cord

Back 59

Elongated extension of the brain acts as the conduit for sensory information to the brain and motor information from the brain

Front 60

Can the spinal cord integrate simple motor responses by itself?

Back 60

Yes, IE reflexes

Front 61

Is the outer side of the spinal cord white or gray matter

Back 61

White matter

(Has motor and senosry axons)

Front 62

Is the inner side of the spinal cord white or gray matter?

Back 62

Gray matter with nerve cellbodies

Front 63

Sensory information enters the spinal cord through the _____

Back 63

Dorsal horn

Front 64

Where are the cell bodies of the sensory neurons located in

Back 64

Dorsal root ganglion

Front 65

All motor information exits the spinal cord through the ______

Back 65

Ventral horn

Front 66

What are fibers like for simple reflexes like the knee-jerk reflex?

Back 66

Sensory fibers (entering through the drosal root ganglion) synapse directly on the ventral horn motor fibers

Front 67

What does the periphernal nervous system consist of

Back 67

Nerves

Ganglia

Front 68

The sensory nerves that enter the CNS and the motor nerves that leave the CNS are part of the ______

Back 68

PNS

Front 69

How many divisions does the PNS have

Back 69

2W

Front 70

What are the two divisions of the PNS

Back 70

*Somatic

*Autonomic

Front 71

What does the somatic nervous system do

Back 71

Innervates skeletal muslce

Voluntary movements

Front 72

What is the autonomic nervous system

Back 72

*Regulates body's internal environment without aid of conscious control

*Both sensory and motor fibers

*Innervates cardiac and smooth muscle

*Helps with blood pressure control, GI motility, excretion, respiration and reproduction because innervates cardiac and smooth muscle

Front 73

What are the two subdivisions of the ANS

Back 73

Sympathetic nervous system

Parasympathetic nervous system

Front 74

What is the sympathetic nervous system

Back 74

"Flight or fight"

-Gets body ready for action in emergency situation

-Increases blood pressure and heart rate

-Increases blood flow to skeletal muslces

-Decreases gut motility

-Dilates the bronchioles ot increase gas exchange

Front 75

What is the neurotransmitter for sympathetic nervous system

Back 75

Norepeinephrine

Front 76

What is the parasympathetic nervous system

Back 76

-Conserve energy and restore the body to resting activity leads after exertion

-Lower heart rate and increase gut motility

Front 77

What is a parasympathetic nerve that innervates many of the thoracic and abdominal viscera

Back 77

Vagus nerve

Front 78

What is the primary neurotransmitter of the parasympathetic nervous system

Back 78

Acetylcholine

Front 79

What does the sympathetic nervous system do to the lens?

Back 79

Nothing

Front 80

What does the parasympathetic nervous system do to the lens

Back 80

Accomondation

Front 81

What does the sympathetic nervous system do to the iris

Back 81

Dilates pupils

Front 82

What does the parasympathetic nervous system do to the pupil?

Back 82

Contstricts the pupils

Front 83

What does the sympathetic nervous system do to the salivary glands

Back 83

Vasoconstriction

Front 84

What does the PNS do to the salivary gland

Back 84

Secretion

Front 85

What does the CNS do to the sweat glands

Back 85

Secretion (specific)

Front 86

What does the PNS do to the sweat glands

Back 86

Secretion (generalized)

Front 87

What does the SNS do to the heart

Back 87

Increase force and rate

Front 88

What does the PNS do to the heart

Back 88

Decreases force and rate

Front 89

What does the SNS do to the peripheral blood vessels

Back 89

Constriction

Front 90

What does the PNS do to the peripheral blood vessels

Back 90

Dilation

Front 91

What does the SNS do to the visceral blood vessels

Back 91

Constriction

Front 92

What does the PNS do to the visceral blood vessels

Back 92

Dilation

Front 93

What does the SNS do to the lungs

Back 93

Vasodilation, brochoconstriction

Front 94

What does the PNS do to the lungs

Back 94

Bronchiodilation, secretion

Front 95

What does the SNS do to the GI tract

Back 95

Decrease peristalsis and secretion

Front 96

What does the PNS do to the GI tract

Back 96

Increase peristalsis and secretion

Front 97

What does SNS do to the rectum and anus

Back 97

Inhibit smooth muscle in rectum and constricts sphincter

Front 98

What does the PNS do to the rectum and anus

Back 98

Increases smooth muscle tone and relaxes sphincterWha

Front 99

What does the SNS do to the adrenal medulla

Back 99

Nothing

Front 100

What does the PNS do to the adrenal medulla

Back 100

Secretion

Front 101

What does the SNS do to the bladder

Back 101

*Relaxation of the detrusor muscle

*Constriction of internal sphincter

Front 102

What does the PNS do to the bladder

Back 102

Constriction of the detrusor muslce and inhibit internal sphincter

Front 103

What does the SNS do to the genitalia

Back 103

Ejaculation

Front 104

What does the PNS do to the genitalia

Back 104

*Penile erection

*Engorgement of clitoris and labia

Front 105

What does the eye do

Back 105

Detects light energy (photons) and transmits information about intensity, color and shape to the brain

Front 106

What is the sclera

Back 106

Covers the eyeball (thick, opaque layer0

Front 107

What is the choroid

Back 107

Beneath the sclera and supplies the retina with blood

Dark pigmented area that reduces reflection in the eye

Front 108

What is the innermost layer of the eye called

Back 108

Retina

Front 109

What does the retina contain?

Back 109

Photoreceptors that sense light

Front 110

What does the cornea do

Back 110

Bends and focuses light rays

Front 111

What is the pupil

Back 111

Opening

Front 112

What is the iris

Back 112

Pigmented muscular structure that contriols diameter of pupil

Front 113

What does the iris respond to

Back 113

Intensity of light in the surroundings

Front 114

Does light make the pupil dialate or constrict

Back 114

Constrict

Front 115

What is the lens

Back 115

Directs light to retina

Front 116

What controls the shape and focal length of the lens

Back 116

Ciliary muslces

Front 117

What are the two types of photoreceptors

Back 117

*Rods

*Cones

Front 118

What are cones

Back 118

REspond to high-intensity illumination and are sensitive to pigments that absorb red, green and blue wavelengths

Front 119

What are the rod pigmeent

Back 119

Rhodopsin

Front 120

What wavelength does rhodopsin absorb

Back 120

Only 1

Front 121

What do the photoreceptor cells synapse onto

Back 121

Bipolar cells

Front 122

What do the bipolar cells synapse onto

Back 122

Ganglion cells

Front 123

What do the axons of the ganglion cells form

Back 123

Optic nerve

Front 124

What does the optic nerve do

Back 124

Conduct visual information to the brain

Front 125

What is the blind spot

Back 125

Where optic nerve exits eye because no photoreceptors there

Front 126

What is the fovea

Back 126

Small area of the retina above the blind spot that is densely packed with cones

Important for high-acuity vision

Front 127

What does the vitreous humor do

Back 127

Helps maintain eye shape and optical properties

Front 128

Is the aqueous or the vitreous more watery

Back 128

Aqueous

Front 129

What space does the aqueous humor fill

Back 129

Between lens and the cornea

Front 130

What is myopia

Back 130

(Nearsightedness)

Image focused in front of the retina

Front 131

What is hyperopia

Back 131

(Farsightedness)

Image behind the retina

Front 132

What is astigmatism

Back 132

Irregularly shaped cornea

Front 133

What is cataracts

Back 133

Lens becomes opaque

Light can't enter eye

Blindness results

Front 134

What is glacoma

Back 134

Increase in eye pressure because of blocking outflow of the aqueous humor which results in optic nerve damage

Front 135

What does the ear transduce

Back 135

Sound energy (pressure waves) into impulses pereived by brain as sound

Front 136

What are the three regions of the ear

Back 136

Outer

Middle

Inner

Front 137

What does the outer ear consist of

Back 137

Auricle (external ear)

Auditory canal

Front 138

What is at the end of the auditory canal

Back 138

Tympanic membrane (ear drum) of the middle ear

Front 139

What are the three bones of the middle ear

Back 139

Malleus

Incus

Stapes

These three make up the ossicles

Front 140

What does the middle ear do

Back 140

Amplify the stimulus and transmit it thorugh the oval window and leads to the fluid filled inner ear

Front 141

What is in the inner ear

Back 141

Cochlea and vestibulur apparatus

Front 142

What is the vetibular apparatus for

Back 142

Maintaining equilibrium

Front 143

What do the vibration of the ossicles do

Back 143

Exert pressure on the fluid in the cochlea stimulating hair cells in the basilar membrane to transduce the pressure into action potentals which travel via the cochlear nerve to the brain for processing