aos1 nervous system functioning

Question 1

central nervous system (CNS)

Answer 1

• a major division of the nervous system comprising of the brain and spinal cord
• received messages from and transmits messages to the peripheral nervous system

Question 2

brain

Answer 2

the organ within the skull that coordinates mental processes and behaviour, and regulates bodily activity

Question 3

spinal cord

Answer 3

nerve tissue which connects the brain to the peripheral nervous system

Question 4

peripheral nervous system

Answer 4

• a major division of the nervous system that transmits neural messages between the CNS and the body
• further divided into the somatic and autonomic nervous system

Question 5

somatic nervous system

Answer 5

• a division of the peripheral nervous system that transmits neural messages related to voluntary motor movement
• comprises of sensory neural pathways and motor neural pathways

Question 6

autonomic nervous system

Answer 6

• a division of the peripheral nervous system that regulates visceral muscles, organs, and glands and transmits neural messages to the CNS
• further divided into the parasympathetic and sympathetic nervous system

Question 7

sympathetic nervous system

Answer 7

• a division of the autonomic nervous system that activates visceral muscles, organs and glands
• prepares the body to respond to a stressor by energising the body to confront the threat

Question 8

parasympathetic nervous system

Answer 8

• a division of the autonomic nervous system that maintains the balanced functioning of visceral muscles, organs, and glands
• maintains homeostasis

Question 9

types of neurons

Answer 9

• motor (efferent) neurons
• sensory (afferent) neurons
• interneurons

Question 10

conscious response

Answer 10

• a deliberate and voluntary action that is initiated by the brain and performed intentionally by the body
• when the sensory receptors detect a stimulus, the sensory neural message is sent to the brain for processing, and then a motor response is initiated

Question 11

unconscious response

Answer 11

• an automatic/involuntary action that is performed without awareness in response to internal and external sensory stimuli
• involved with the autonomic nervous system
• e.g. heart rate increasing, breathing rate increasing

Question 12

spinal reflex

Answer 12

an unconscious response to sensory stimuli that is initiated by interneurons in the spinal cord INDEPENDENT of the brain

Question 13

process of spinal reflex

Answer 13

• a harmful sensory stimulus is detected by sensory receptors
• sensory neurons transmit this message to the spinal cord
• an interneuron in the spinal cord relays the message to a motor neuron
• skeletal muscles carry out this unconscious response
• the sensory message continues to travel to the brain and is processed after the response

Question 14

neural synapse

Answer 14

the region that includes the axon terminals of the presynaptic neuron, the synaptic gap, and the dendrites of the postsynaptic neuron

Question 15

axon terminal

Answer 15

the end of the neuron that releases neurochemicals into the neural synapse

Question 16

neurotransmitter

Answer 16

a chemical molecule that has an effect on one or two postsynaptic neurons

Question 17

excitatory neurotransmitter

Answer 17

• has excitatory effects on the postsynaptic neuron, meaning it increases the likelihood of the neuron firing an action potential
• an example is glutamate, which has a role in learning and memory

Question 18

inhibitory neurotransmitter

Answer 18

• decreases the likelihood of the postsynaptic neuron firing an action potential
• an example is gamma aminobutyric acid (GABA), which plays a role in preventing the overexcitement of neurons, seizures and reducing anxiety

Question 19

neuromodulators

Answer 19

• a chemical molecule that have an effect on multiple postsynaptic neurons
• they can effect neurotransmitters by enhancing the excitatory or inhibitory effects of neurotransmitters and changing the neurotransmitter release pattern

Question 20

serotonin

Answer 20

• a neuromodulator primarily responsible for the regulation of mood and sleep
• has inhibitory effects on the postsynaptic neuron

Question 21

dopamine

Answer 21

• a neuromodulator primarily responsible for voluntary motor movement, the experience of pleasure, and reward-based learning
• can have both excitatory and inhibitory effects on the postsynaptic neuron depending on the type of receptor sites

Question 22

synaptic plasticity

Answer 22

the ability of synaptic connections to change over time in response to activity or experience

Question 23

sprouting

Answer 23

the ability of dendrites or axons to develop new extensions or branches
this increases the reach of the neuron and enables the formation of new synaptic connections

Question 24

rerouting

Answer 24

the ability of a neuron that is connected to a damaged neuron to create an alternative synaptic connection with an undamaged neuron

Question 25

pruning

Answer 25

the elimination of synaptic connections that are not adequately activated
this allows for stronger and more essential synaptic connections

Question 26

long term potentiation

Answer 26

• the long-lasting and activity-dependent strengthening of synaptic connected that are regularly fired together
• results in structural changes such as… increased number of receptor sites on the dendrites, bushier dendrites and increased number of synaptic connections between neurons (sprouting)
• “neurons that fire together, wire together”

Question 27

long-term depression

Answer 27

• the long lasting and activity dependent weakening of synaptic connections between neurons that are not regularly coactivated
• results in structural changes such as… decreased number of receptor sites on the dendrites, decreased number of dendrites and decreased number of synaptic connections between neurons (pruning)