AOS1 - nervous system functioning

Question 1

what are the three main functions of the nervous system?

Answer 1

receive info, process info and coordinate a response to information

Question 2

what two things make up the central nervous system?

Answer 2

the brain and the spinal cord

Question 3

what are the two functions of the spinal cord?

Answer 3

1. receive sensory info from the body via the PNS and send those messages to the brain for processing
2. receive motor info from the brain and send it to relevant parts of the body

Question 4

what are the two functions of the PNS?

Answer 4

1. carry info to the CNS from muscles, glands and organs
2. carry messages from the CNS to the bodies muscles, organs and glands

Question 5

what four NS’s make up the PNS?

Answer 5

somatic, autonomic –> sympathetic and parasympathetic

Question 6

what is the function of the somatic NS?

Answer 6

carries sensory info TO the CNS and motor info AWAY from the CNS
(SAME: sensory afferent, motor efferent)

Question 7

what is the function of autonomic NS?

Answer 7

connects the CNS to the body’s internal organs and glands, providing feedback to the brain about their activity

Question 8

what is the function of sympathetic NS?

Answer 8

activates internal muscles, organs and glands to prepare the body for vigorous activity or to deal with stressful or threatening situations

Question 9

what is the function of the parasympathetic NS?

Answer 9

helps to maintain the internal body environment in a steady, balanced state i normal functioning. restores the body to a state of calm and maintains homeostasis

Question 10

what is a conscious response?

Answer 10

a reaction to a sensory stimulus that involves awareness, a voluntary reaction. controlled by the somatic NS

Question 11

what is an unconscious response?

Answer 11

a reaction to a sensory stimulus that does involve awareness, an unintentional, automatic reaction. controlled by the autonomic NS

Question 12

what are the six steps of the spinal reflex?

Answer 12

1. receptor cells detect stimulus and send a neural message to a sensory neuron
2. sensory neuron carries message to the spinal cord
3. interneuron in spinal cord relays message to a motor neuron
4. motor neuron carries message to muscles causing a withdrawal reflex
5. while the spinal reflex, the message is sent to the brain through the spinal cord
6. the message is received by the brain and the pain is interpreted

Question 13

what is a neuron?

Answer 13

an individual nerve cell specialised to receive, process and transmit information

Question 14

role of the dendrite?

Answer 14

detect and receive information from other neurons

Question 15

role of the axon?

Answer 15

transmits neural information to other neurons

Question 16

role of myelin/myelin sheath?

Answer 16

promote efficient transmission of information

Question 17

role of axon terminals and buttons?

Answer 17

store and secrete neurotransmitter

Question 18

what is a motor neuron?

Answer 18

an efferent neuron that carries messages from the CNS to skeletal and visceral muscles to stimulate activity or response

Question 19

what is a sensory neuron?

Answer 19

an afferent neuron that received messages from both the bodies internal and external environments and transmits it to the CNS

Question 20

what is an interneuron?

Answer 20

a neuron that sends messages sensory and motor neurons within the CNS

Question 21

what is a synaptic gap?

Answer 21

a tiny space between the terminal buttons of one neuron and the dendrites of another where the neurotransmitter secreted from the buttons is received by the dendrite

Question 22

what is a synapse?

Answer 22

the site where the communication occurs between adjacent neurons

Question 23

what is neurotransmitter?

Answer 23

a chemical substance produced by a neuron that carries a message to other neurons or cells

Question 24

what is glutamate?

Answer 24

the CNS’s main excitatory neurotransmitter. it increases the likelihood of the post-synaptic neuron firing

Question 25

what gamma-amino butyric acid (GABA)?

Answer 25

the CNS’s main inhibitory neurotransmitter. it decreases the likelihood of the post-synaptic neuron firing

Question 26

explain the lock and key process

Answer 26

as every neurotransmitter has a chemically distinct shape, it will search for the correctly shaped receptor site on the dendrites of the adjacent neuron

Question 27

what is parkinsons disease?

Answer 27

a slow developing neurodegenerative disease that can affect both motor and non-motor functions.

Question 28

list four motor symptoms of parkinsons

Answer 28

1. tremors
2. bradykinesia
3. muscle rigidity
4. postural instability

Question 29

what is bradykinesia?

Answer 29

slowness or involuntary movements

Question 30

list three non-motor symptoms of parkinsons

Answer 30

1. sensitivity to temperature
2. loss of sense of smell
3. cognitive functioning issues such as slowed thinking, impaired problem solving etc.

Question 31

what is believed to cause the motor symptoms?

Answer 31

degeneration and loss of neurons in the substantia nigra

Question 32

where is the substantia nigra located?

Answer 32

in the basal ganglia found in the midbrain

Question 33

what neurotransmitter does the SN produce?

Answer 33

dopamine