Nervous System

Front 1

Neuron

Back 1

A single nerve cell

Front 2

Name 6 parts of a neuron

Back 2

Cell body

Axon

Axon hillock

Dendrites

Myelin Sheath

Synaptic ending/bulbs

Front 3

What does the cell body contain?

Back 3

Nucleus, cytoplasm and other organelles.

Front 4

Nissl Bodies

Back 4

Granular material conmposed of many ribosomes and rough E.R

Front 5

What is the cytoplasm in axon called?

Back 5

Axoplasm

Front 6

What do axons lack?

Back 6

Free ribosomes & nissl Bodies

Front 7

Axon

Back 7

One thin tube like process arising from cell body that condicts electricity away from cell body

Front 8

Which component of a neuron cobtains most of the cytoplasm?

Back 8

Axon

Front 9

Axon Hillock

Back 9

End of soma, controls generation of action potential ie. Nerve signal

Front 10

Dendrites

Back 10

Receive excitation from other neurons, spiny in appearance. Carries signals toward cell body

Front 11

What is another name for dendrites and axons?

Back 11

Fibers or processes

Front 12

Synaptic Ending/Bulbs

Back 12

Ends of axon that release transmitter substances to propagate signal to othr neuron

Front 13

What are four shapes of neuron?

Back 13

Unipolar, bipolar, pseudopolar, multipolar

Front 14

What are 3 type of neurons?

Back 14

Sensory neuron

Motor neuron

Interneuron

Front 15

Sensory Neuron

Back 15

Brings nerve impulse from sensory organs to central nrrvous system

Front 16

Motor Neuron

Back 16

Condicts nerve impulse from central nervous system to effector (muscle fibre or gland)

Front 17

Interneuron

Back 17

Found only within central nervous system. Relays nerve impulse between neurons in CNS

Front 18

Neuroglial/Glial Cells

Back 18

Provide nutrition, support, communication and protection between neurons.

Front 19

What ate two types of neuroglial cells and wgere sre they found?

Back 19

Schwann Cell: in perepheral nervous system

Oligodendrpcyte: central nervous system

Front 20

What is another name for a Schwann cell?

Back 20

Neurolemmocyte

Front 21

Myelin Sheath

Back 21

Rich in lipid
Schwann cells and oligodendrocytes circling the axons forming this sheath

Front 22

What property do Schwann cells and oligodendrocytes provide axons?

Back 22

They encircle axons insulating them electrically

Front 23

Neurolemma

Back 23

outermost layer of Schwann cells surrounding neurons

Front 24

What role do neurolemma play in the healing of nerves?

Back 24

Does not degenerate after nerve injury but forms template for nerves to heal in PNS

Front 25

Nodes of Ranvier

Back 25

gaps between Schwann cells

Front 26

The distance between the nodes of Ranvier are called _________

Back 26

Internodes

Front 27

How does the myelin sheath affect the electrical current across the axoplasm?

Back 27

It increases the speed of propagation of electrical signal

Front 28

Saltatory Conduction

Back 28

propagation of electrical currents across the axoplasm from one node of Ranvier to the next

Front 29

What is used to measure electrical potential difference (voltage) between outside and inside of a neuron?

Back 29

Oscilloscope

Front 30

Describe the charge of a neuron

Back 30

The inside of an axon is more negative compared to the outside

Front 31

Resting Potential

Back 31

refers to the neuron having a negative membrane at rest

Front 32

Describe the concentration of Na ions and K ions inside and outside of an axon

Back 32

There is a higher concentration of K ions on the inside of the axon than outside and a lower concentration of Na ions on the inside than outside

Front 33

Aside from the concentrations of Na ions and K ions, what else affects the charge within an axon?

Back 33

higher concentration of negative organic ions (proteins) inside the cell than outside

Front 34

Is membrane more permeable to Na ion or K ion?

Back 34

K ion

Front 35

What factor of the axomembrane contributes to its charge?

Back 35

It is more permeable to K ions than Na ions. Since there is a lower concentration of K ions on outside, more K ions will leave the cell, crossing the axomembrane. this makes it so there are less positive charges on the inside than outside which in turn makes the interior of the axon have a negative charge

Front 36

What is the rate of ions being pumped in and out?

Back 36

3 Na ions out for every 2 K ions in, to maintain a potential difference of more + charge on the outside than in which contributes to resting membrane potential

Front 37

What causes the axomembrane to go from a negative charge to a positive charge?

Back 37

Stimulation o neuron causes axomembrane to increase its permeability to Na ions by opening up gates of Na+ channels
Na ions move into cell because there is a higher concentration of Na ions on outside of cell than inside and because of negative ions on inside of axon
this causes the inside of membrane to turn + also known as depolarization

Front 38

Refractory Period

Back 38

Period where another action potential cannot occur due to membrane potential being positive, period follows immediately after stimulation where nerve is unresponsive to further stimulation

Front 39

What causes the axomembrane to go from a positive charge to a negative charge? Also known as repolarization

Back 39

Na ion channels close and K ion gates open in mebrane
K ions move outside of cell due to concentration gradient and repulsive forces due to excess of positive charge inside axon

Front 40

Hyperpolarization

Back 40

Resting membrane potential becomes more negative than normal due to K ion pump being open longer than it should be

Front 41

Nerve Impulse

Back 41

Due to stimulation of neuron and changing of polarity across axomembrane

Front 42

How do myelenated fibers affect nerve impulses?

Back 42

Due to distances between nodes of Ravier

Front 43

At which parts of the neuron does synapsing occur?

Back 43

The axon and dendrite

Front 44

Which part of the axon is involved in synapses?

Back 44

Synpatic bulb (axonal ending)

Front 45

What do synaptic bulbs contain?

Back 45

Vesicles with neurotransmitters

Front 46

Synaptic Cleft

Back 46

gap between pre-synaptic membrane and post synaptic membrane, gap junction can also exist

Front 47

Describe the process of snyapses

Back 47

1. Nerve impulse reaches pre synaptic membrane, opens up calcium ion gates
2. Calcium ion enters presynaptic bulb and reactions occur causing neurotransmitter to be released into synaptic cleft
3. Neurotransmitters diffuse across synaptic cleft and bind to receptors on post synaptic cleft
4. causes change in membrane potential of post synaptic cell which results in excitation or inhibition of post synaptic membrane

Front 48

How does a neurotransmitter cause a nerve to become excited?

Back 48

Makes post synaptic membrane potential less (Decrease its negativity), called EPSP. Allows more Na ions to come inside cell

Front 49

How does a neurotransmitter cause a nerve to become inhibited?

Back 49

Makes post synaptic membrane potential increase (more negative) IPSP

Front 50

What does an EPSP have to do to cause an action potential?

Back 50

1. Be great enough to reach threshold potential (-50mV)
2. Spread to axon hillock

Front 51

Summation

Back 51

net effect of all excitatory and inhibitory neurotransmitters the cell receives

Front 52

What is the all or none response?

Back 52

The strength of stimulus does not affect the strength of which a nerve or muscle fibre responds. It only matters if the voltage reaches the threshold or not

Front 53

Name 5 nerotransmitters

Back 53

Acetylcholine, norepinephrine, serotonin, dopamine and GABA

Front 54

What type of molecules are neurotransmitters?

Back 54

aminoacids, peptides or even gases

Front 55

What happens to neurotransmitters once the receptors of the post synaptic nerve releases them?

Back 55

They are destroyed by enzymes in synapse or taken up by post or pre synaptic membrane to be repackaged or destroyed to prevent overstimulation or overinhibition

Front 56

What is the function of acetylcholinesterase?

Back 56

break down actycholine

Front 57

MAO

Back 57

monoamine oxidases break down serotonin, norepinephrine, and dopamine

Front 58

Where are neurotransmitters created?

Back 58

in cell body, soma

Front 59

Central Nervous System

Back 59

neurons only found in brain and spinal cord

Front 60

Peripheral Nervous System

Back 60

Nerves connected to CNS but resides outside of CNS

Front 61

Which group of nerves is the PNS made of?

Back 61

cranial, spinal and of the autonomic N.S

Front 62

Nerves

Back 62

bundles of neurons with their cell bodies found in CNS or in ganglia

Front 63

Ganglia

Back 63

collection of nerve cell bodies outside of CNS

Front 64

What two groups is the PNS divided into?

Back 64

Somatic (voluntary control)
Autonomic (involuntary control)

Front 65

Cranial Nerves

Back 65

connect to brain

Front 66

How many cranial nerves are there?

Back 66

12 pairs

Front 67

What are 5 types of spinal nerves?

Back 67

Cervical
Thoracic
Lumbar
Saccral
Coccygeal

Front 68

Where a spinal nerves found?

Back 68

come out between vertebrae of spine

Front 69

Are spinal nerves somatic or autonomic?

Back 69

Both

Front 70

Are spinal nerves motor or sensory?

Back 70

Both

Front 71

Where do sensory fibres enter the spinal cord?

Back 71

Dorsal root

Front 72

Where do motor fibres exit spinal cord?

Back 72

Ventral root

Front 73

What is responsible for reflex responses?

Back 73

Spinal nerves, both sensory and motor

Front 74

Which nerves are known as mixed nerves?

Back 74

Spinal nerves

Front 75

Where do you find cerebrospinal fluid?

Back 75

central canal of spinal cord, ventricles of brain and separating meninges

Front 76

What is cerebrospinal fluid for?

Back 76

nourishment to nerve cells
shock absorber
cleansing CNS of metabollic waste

Front 77

Meninges

Back 77

layers of connective tissues that protects spinal cord

Front 78

Reflex Arc

Back 78

nerve pathway that carries out reflex

Front 79

Describe the process of a reaction

Back 79

Receptor activated ---> sensory neuron ---> dorsal root----> dorsal cord ---> interneuron ----> ventral cord ----> motor neuron ---> effector (muscle or gland)

Front 80

Autonomic Nervous System

Back 80

involuntary unconscious control

Front 81

What does the autonomic nervous system control?

Back 81

smooth muscle, internal organs and glands of body

Front 82

Does autonomic nervous system have motor or sensory neurons?

Back 82

motor

Front 83

What is the autonomic nervous system divided into?

Back 83

Sympathetic and parasympatheticq

Front 84

Which type of neurons send information about state of organs to CNS? and what responds to this?

Back 84

Sensory neurons in somatic nerves.
autonomic nerve system then causes changes in target organ they supply

Front 85

What type of neuron does the sympathetic nervous system have?

Back 85

short myelenated ---> ganglai ----> long unmyelenated

Front 86

What type of neuron does the parasympathetic nervous system have?

Back 86

long myelenated ---> ganglai ----> short unmyelenated

Front 87

When does the sympathetic nervous system activate?

Back 87

During emergency situations, fight or fligth

Front 88

Where do cell bodies of the pre-synaptic cell lie?

Back 88

thoracic and lumbar part of spinal cord

Front 89

Describe the structure of the sympathetic nerves

Back 89

1. cell bodies in thoracic and lumbar parts of spinal cord
2. axons exit cord and run to ganglia near cord where they synapse with post synaptic neurons whose cell bodies lies within sympathetic ganglion found within sympathetic trunk

Front 90

What is the neurotransmitter released by postganglionic neuron?

Back 90

norapinephinerine

Front 91

What does the parasympathetic system cause?

Back 91

internal body responses associated with relaxtion

Front 92

What is the neurotransmitter on postganglionic neuron?

Back 92

acetylcholine

Front 93

Where are the cell bodies of pre-synaptic neurons in the parasympathetic nervous system found?

Back 93

Medulla and from sacral regions of spinal cord

Front 94

Where does the synapse occur between the post synaptic neuron and pre synaptic neuron?

Back 94

Near or inside organs

Front 95

Most but not all organs are innervated by both systems, true or false

Back 95

true

Front 96

Which organs are only innervated by the sympathetic nervous system?

Back 96

adrenal medulla and sweat glands

Front 97

What layer protects the brain?

Back 97

Meninges

Front 98

Meningitis

Back 98

infection of meninges

Front 99

What are the 4 parts of the brain stem

Back 99

midbrain, pons and medulla

Front 100

What is the basic life support centre of the body?

Back 100

Brain stem

Front 101

what is known as "primitive brain"?

Back 101

brain stem

Front 102

Medulla

Back 102

1. Regulates heartbeat
2. breathing
3. vasoconstriction
3. reflex centre, vomiting, sneezing, coughing, hiccuping, swallowing

Front 103

Pons

Back 103

1. Reflex centre for head movement in response to visual and auditory stimuli
2. regulates breathing rate with medulla

Front 104

Midbrain

Back 104

Reflex centre for visual, auditory, and tactile responses

Front 105

Diencephalon

Back 105

made of thalamus and hypothalamus
regulates body functions and emotions

Front 106

Hypothalamus

Back 106

1. Control centre for all autonomic regulatory activity in body
2. maintains homeostasis
3. regulates hunger, sex drive, sleep, thirst, body temperature, water balance, blood pressure
4. controls pituitary gland, connection between nervous and endocrine system
5. makes ADH (vasopressin) and oxytocin by neurosecretory neurons which are stored in posterior pituitary gland

Front 107

Thalamus

Back 107

1. Relay station, taking sensory information from all body processes and sends information to appropriate parts of brain
2. regulates states of sleep, arousal or wakefulness (damage causes coma)

Front 108

What is known as the master gland?

Back 108

Pituitary glands since it controls many functins of other glands

Front 109

What type of hormones are secreted by the neurosecretory cells into the posterior pituitary gland?

Back 109

ADH (antidiuretic) aka vapopressin
Oxytocin

Front 110

What are the effects of ADH?

Back 110

promotes reabsorbtion of water by collecting ducts of kidneys and constriction of arterioles

Front 111

What are the effects of oxytocin?

Back 111

contraction of uterus and release of milk from mammary glands

Front 112

Cerebellum

Back 112

coordinates movement
processes info from inner ear to maintain balance
posture

Front 113

Cerebrum

Back 113

largest part of brain
consciousness
higher brain centre
memory
attention
perceptual awareness
thought
language

Front 114

What is the outer layer of the cerebrum called?

Back 114

cerebral cortex

Front 115

Cerebral Cortex

Back 115

gray matter, cell bodies and short unmyelinated fibres

Front 116

White matter

Back 116

axons and myelinated fibres

Front 117

What is the cerebrum joined together by?

Back 117

corpus callosum

Front 118

What are the 3 areas that the cerebrum has?

Back 118

association
motor
sensory

Front 119

Association area

Back 119

Takes in info to make sense out of it

Front 120

What controls voluntary activity in cerebrum?

Back 120

basal nucleii in cortex

Front 121

What stimulates the adrenal glands?

Back 121

ANS and indirectly by hypothalamus

Front 122

Which hormones are released by adrenal cortex at times of stress? and what do they do?

Back 122

mineralocorticoids and glucocorticoids
regulates amount of minerals and glucose in blood

Front 123

Which hormones are released by adrenal medulla and when?

Back 123

Epinephrine (adrenaline) and norepinephrine (noradrenaline), during emeregncy situations

Front 124

What controls adrenal medulla?

Back 124

ANS

Front 125

What are the effects of epinephrin and norepinephrine on body?

Back 125

1. metabollic rates goes up
2. blood glucose level goes up
3. bronchioles dilate to increases rate of breathing
4. blood vessels in skin and digestive tract constrict while those in skeletal muscles dilate
5. heart rate goes up and cardiac muscle contracts with more force