aos 1 : nervous systems and neutrons

Question 1

nervous system

Answer 1

a network of neurons that coordinate actions and transmit signals between different parts of the body, it consists of 2 divisions; Central NS & peripheral NS.

Question 2

brain

Answer 2

responsible for memory, attention, concentration, language, spatial skills

Question 3

spinal cord

Answer 3

3 major functions;

1. transmits sensory information from PNS to brain
2. transmits motor information from brain to PNS enabling movement
3. reflex arc

Question 4

sensory neurons

Answer 4

aka afferent neurons, send sensory info (from environment) from sense organs (skin receptors, eyes, ears etc) to the brain via the spinal cord (central NS) for further processing

Question 5

motor neurons

Answer 5

aka efferent neurons, sends motor info (originating in primary motor cortex) via spinal cord to skeletal muscles in PNS enabling voluntary movement.

Question 6

interneurons

Answer 6

can only be found in the CNS; they integrate information with other neurons ie. sensory and motor

Question 7

dendrites

Answer 7

are the branched projections of neurons that receive input from other neurons

Question 8

synapse

Answer 8

a junction that permits a neutron to pass on a chemical signal to another cell

Question 9

neurotransmitters

Answer 9

chemicals which allow transmission of signals from 1 neutron to another

Question 10

soma

Answer 10

the cell body which contains most of the cells genetic material

Question 11

axon

Answer 11

a long projection of a neutron that conducts electrical impulses away from the soma

Question 12

PNS

Answer 12

contains all the neurons outside the CNS

Question 13

CNS

Answer 13

division of the NS which processes and interprets incoming information, stores memories, sends out neural information that initiates actions; made up of brain and spinal cord

Question 14

somatic NS

Answer 14

a division of the PNS, responsible for voluntary movement & transmission of sensory information to CNS

Question 15

autonomic NS

Answer 15

division of PNS which connects CNS to visceral muscles, which keeps vital organs going with conscious thought

Question 16

visceral muscles

Answer 16

muscles that regulate the internal organs (without conscious thought) eg. heart, lungs

Question 17

skeletal muscles

Answer 17

muscles attached to bones, which require a command from the brain (motor cortex) to move

Question 18

sympathetic NS

Answer 18

a division of the autonomic NS which prepares the body for action, by increasing the body physiological arousal when the organism is under threat

Question 19

parasympathetic NS

Answer 19

a division of the PNS which counterbalances the effects of the sympathetic NS and maintains an optimum level of functioning during low stress times

Question 20

homeostasis

Answer 20

a steady internal body environment, that is maintained by the parasympathetic NS during low stress times

Question 21

myelin

Answer 21

a white fatty substance that protects the axon and enhances the transmission of the electrical impulse

Question 22

neurons

Answer 22

the core components of the NS

Question 23

receptors

Answer 23

the structures on the dendrites neurons that recognise and bind specific neurotransmitters

Question 24

neurohormone

Answer 24

similar to a neurotransmitter but it can be released into the bloodstream or in the brain via a presynaptic neuron

Question 25

glutamate

Answer 25

the most abundant excitatory neurotransmitter in the CNS. it plays a key role in learning (LTP), memory, thinking and movement

Question 26

GABA

Answer 26

the most abundant inhibitory neurotransmitter in the CNS. it regulates arousal, by counteracting the effects of glutamate

Question 27

dopamine

Answer 27

a neurotransmitter that plays a key role in pleasure, reinforcement, movement, dependancy

Question 28

inhibitory

Answer 28

when these types of neurotransmitters bind with postsynaptic neurons, they Arte less likely to fire an action potential

Question 29

excitatory

Answer 29

when these types of neurotransmitters bind with postsynaptic neurons, they are more likely to fire an action potential

Question 30

presynaptic

Answer 30

the sending neuron

Question 31

postsynaptic

Answer 31

the receiving neuron

Question 32

vesicles

Answer 32

storage sites of neurotransmitters that can be found in axon terminals