CHAPTER 2 - nervous system functioning

Question 1

role of the central nervous system (CNS)

Answer 1

process info from body’s internal and external environments and activate appropriate responses

Question 2

features of CNS:

Answer 2

spinal cord and the brain

Question 3

roles of the spinal cord:

Answer 3

• receive sensory information from body and send to brain
• receive motor info from brain and send to relevant parts of the body

Question 4

role of peripheral nervous system (PNS)

Answer 4

• carries info from internal environment to CNS
• info from CNS to body’s internal organs/muscles

Question 5

subdivisions of PNS:

Answer 5

somatic nervous system and autonomic nervous system

Question 6

roles of somatic nervous system

Answer 6

• carries sensory info to CNS and motor info from CNS to muscles etc
• voluntary actions (skeletal muscles)

Question 7

autonomic nervous sytem roles

Answer 7

• connects CNS to body’s internal organs
• self regulating bodily functions (involuntary)

Question 8

divisions of the autonomic nervous system:

Answer 8

sympathetic, parasympathetic, enteric nervous systems

Question 9

role of the sympathetic nervous system

Answer 9

• activates internal muscles, organs and glands to prepare the body for stressful or threatening situations

Question 10

sympathetic activation when stressor process:

Answer 10

perceived emergency - adrenal glands release adrenaline/cortisol

Question 11

effects of sympathetic activation:

Answer 11

increased heart rate, increased blood pressure, sweat produced

Question 12

role of the parasympathetic nervous system:

Answer 12

helps maintain a normal level of functioning/return body to a state of homeostasis

Question 13

parasympathetic or sympathetic is more dominant:

Answer 13

parasympathetic

Question 14

roles of neurons & ganglia in enteric nervous system

Answer 14

• detect physiological condition of gastrointestinal tract
• control gut movement
• nutrient management

Question 15

where is the enteric nervous sytem

Answer 15

• embedded in the walls of the gastrointestinal tract, composed of clusters of neurons called ganglia
• mouth, oesophagus, stomach, both intestines

Question 16

spinal reflex definition

Answer 16

• an unconscious, automatic response to a certain stimuli initiated bye the spinal cord
• independant of brain

Question 17

process of spinal reflex:

Answer 17

sensory neurons (afferent) go up somatic NS, reach spinal cord which relays message immediately initiated by interneurons which send motor neurons to remove body part from stimuli

Question 18

conscious response definition:

Answer 18

reaction to a stimuli involving awareness, attention will have been paid to the stimulus

Question 19

conscious response involves which response?

Answer 19

a voluntary response (involves awareness)

Question 20

unconscious response definition:

Answer 20

reaction to a stimuli not involving awareness
- bodily responses regulated by the ANS occur automatically in response to stimuli about state of bodily systems

Question 21

how do neurons communicate?

Answer 21

by sending neurotransmitters between synaptic gap of a terminal button of one and the dendrites of another

Question 22

presynaptic neurons:

Answer 22

send info

Question 23

postsynaptic neurons:

Answer 23

receive info

Question 24

neurotransmitters definition

Answer 24

chemical messengers produced by a neurone that carry messages to other neutrons

Question 25

lock and key model:

Answer 25

neurotransmitters binds itself to complimentary receptor site of postsynaptic neuron

Question 26

in presynaptic neuron, NTs are within

Answer 26

vesicles

Question 27

what is reuptake?

Answer 27

when a NT doesn't bind to receptors of postsynaptic neuron and so are absorbed back to terminal button of presynaptic

Question 28

excitatory effect of NT:

Answer 28

stimulate/activate postsynaptic neuron to perform their function

Question 29

inhibitory effect of NT:

Answer 29

block/prevent postsynaptic neuron from firing

Question 30

what is glutamate?

Answer 30

the main excitatory NT in the CNS, involved in aspects of brain functioning, learning and memory

Question 31

excitatory effect of glutamate promotes what:

Answer 31

promises growth/strengthening of synaptic connections of neurons within a neural pathway - (too much is bad)

Question 32

what is Gabba Amino Butyric Acid (GABA)?

Answer 32

the primary inhibitory NT of the CNS, involved in fine-tuning neural transmission in the brain to maintain optimal neurotransmission level

Question 33

what can happen without GABA?

Answer 33

postsynaptic neurons get out of control, causing seizures and anxiety symptoms

Question 34

neuromodulators definition:

Answer 34

chemical messenger that changes the reactivity of another NTs to enhance inhibitory or excitatory effect

Question 35

do neuromodulators release into one synapse?

Answer 35

no, they're released into a broad area impacting hundreds of thousands of synapses

Question 36

what is dopamine?

Answer 36

a modulatory neurotransmitter with roles in voluntary movement, pleasure, petite and memory (reward based learning)

Question 37

is dopamine excitatory of inhibitory?

Answer 37

primarily excitatory, with inhibitory effects in different areas

Question 38

where is dopamine released? what is involved

Answer 38

from the substantia nigra, involved in coordinated muscle movement

Question 39

what happens with a diminished substantia nigra?

Answer 39

secretes dopamine, diminished substantia nigra leads to stiff muscles movements and potentially Parkinson's disease

Question 40

what is serotonin?

Answer 40

a modulatory neurotransmitter with roles in mood, appetite, emotional processing, sleep onset and pain perception

Question 41

is serotonin inhibitory or excitatory?

Answer 41

serotonin is only inhibitory that helps balance the effects of other neurotransmitters

Question 42

specific role of serotonin:

Answer 42

act as a mood stabiliser, low levels of it are associated with depression and less pleasurable experiences

Question 43

serotonin and sleep:

Answer 43

important in sleep-wake cycle and increases feelings of wakefulness during the day

Question 44

what is serotonin syndrome?

Answer 44

occurs with too much serotonin and elevated heart rate and wakefulness, leads to seizures

Question 45

synaptic plasticity definition:

Answer 45

refers to the ability of a synapse to change in response to experiences

Question 46

synaptic plasticity allows for:

Answer 46

long term depression and long term potentiation (strengthening of continual used synaptic connections OR weakening of unused synaptic connections)

Question 47

sprouting is:

Answer 47

creation of new synapses on a neuron to make connections with other neurons

Question 48

rerouting is:

Answer 48

occurs when new connections are made between neurons create alternative neural pathways

Question 49

pruning is:

Answer 49

the elimination of weak or unused synapses "use it or lose it"

Question 50

sprouting, rerouting, pruning can occur after:

Answer 50

occur after brain injury or lost brain function to maximise remaining functions

Question 51

Hebb rule:

Answer 51

the more you perform a task, the stronger neural connection is at the synapse (associated with learning)

Question 52

long term potentiation is:

Answer 52

the strengthening of neural connections after repeated, high frequency transmission

Question 53

LTP allows:

Answer 53

- communication of neurons easier - neurons are more responsive

Question 54

long term depression is:

Answer 54

the long lasting decrease in the strength of synaptic transmission of neural responses occurring from a lack of stimulation