Biopsychology - neurons and synaptic transmissions

Question 1

dendrite

Answer 1

branch out from the cell body and receives messages from neighbouring neurons because they have receptor sites

Question 2

axon

Answer 2

carries messages from cell body down length of neuron
covered in fatty tissue called myelin sheath, which allows electrical impulses to be transmitted most efficiently

Question 3

axon terminal

Answer 3

releases neurotransmitters to be sent on to the next neuron from the vesicles of neurotransmitters

Question 4

how do neurons send messages through cells

Answer 4

electrically

Question 5

how do neurons send messages between cells

Answer 5

chemically

Question 6

action potential

Answer 6

electrical impulse that triggers release of neurotransmitters

Question 7

what are the three types of neuron

Answer 7

sensory, relay and motor

Question 8

structure of sensory neuron

Answer 8

long dendrites and short axons
cell body at top
carries messages from sensory receptors to CNS
part of PNS

Question 9

structure of relay neuron

Answer 9

short dendrites, short axons
cell body in centre
connect sensory neurons to motor neurons
part of the CNS, in spinal cord

Question 10

synaptic cleft

Answer 10

gap between neurons

Question 11

presynaptic terminal

Answer 11

sending neuron

Question 12

postsynaptic terminal

Answer 12

receiving neuron

Question 13

excitatory effect

Answer 13

creates positive charge, increasing likelihood of neuron firing and passing on a message (cause action potential)
adrenaline is an example

Question 14

inhibitory effect

Answer 14

negatively charged
decreasing likelihood of neuron firing and passing on a message (stops action potential)
serotonin is an example

Question 15

summation

Answer 15

total of charge from neurotransmitters being received by a neuron at a time

Question 16

reflex arc

Answer 16

stimuli is detected in PNS
carried by sensory neuron to relay neuron in CNS
carried by motor neuron to effectors so response can be made

Question 17

why is the conscious brain not involved in reflex arcs

Answer 17

it would cause the reaction to take more time, meaning the body is at risk

Question 18

synaptic transmission

Answer 18

messages are transmitted as electrical impulses (action potential)
action potential triggers the release of neurotransmitters
neurotransmitters diffuse across synapctic cleft to receptor sites of postsynaptic terminal
at receptor site, neurotransmitters are converted back to an electrical impulse