biopsych; neurons and synaptic transmission - Y12

Question 1

how are signals transmitted?

Answer 1

electrically and chemically

Question 2

what is a neuron?

Answer 2

the basic building blocks of the nervous system, neurone are nerve cells that process and transmit messages through electrical and chemical signals

Question 3

what is a sensory neuron?

Answer 3

these carry messages from the PNS to the CNS which long dendrites and short axons

Question 4

what is a relay neuron?

Answer 4

these connect the sensory neurons. to the motor or other relay neurons. they have short dendrites and short axons

Question 5

what is a motor neuron?

Answer 5

these connect the CNS to the effectors sun as muscles and glands. they have short dendrites and long axons

Question 6

what does EPSP stand for

Answer 6

excitatory postsynaptic potential

Question 7

what does IPSP stand for

Answer 7

inhibitory postsynaptic potential

Question 8

what do dendrites do?

Answer 8

carry nerve impulses from the adjacent neurons towards the cell body

Question 9

what is the soma?

Answer 9

the cell body that includes a nucleus which contains the genetic material of the cell

Question 10

what does the axon do?

Answer 10

carries the impulses away from the cell body down the length of the neuron

Question 11

what is the myelin sheath?

Answer 11

a fatty substance that covers and protects the axon and speeds up electrical transmission of the impulse.

Question 12

what are the Nodes of Ranvier?

Answer 12

gaps between the myelin sheath which speed up the transmission by forcing them to jump across the gap.

Question 13

what is the terminal button?

Answer 13

the bottom of the axon which is where the neuron communicates with the postsynaptic neuron through the synaptic cleft.

Question 14

what is electrical transmission?

Answer 14

when the neuron is activated by the stimulus, the inside of the cell becomes positively charged causing action potential to occur which creates an electrical impulse to travel down the axon towards the end of a neuron.

Question 15

what is synaptic transmission?

Answer 15

the process by which neighbouring neurons communicate with each other by sending chemical messages across the gap which separates them.

Question 16

what is a neurotransmitter?

Answer 16

brain chemicals which are released from synaptic vesicles that relay signals across the synapse from one neuron to another. they can be divided into excitatory or inhibitory neurotransmitters

Question 17

what is excitation?

Answer 17

when a neurotransmitter increases the positive charge of the neuron making it more likely to fire and pass on the impulse

Question 18

what is inhibitory?

Answer 18

when a neurotransmitter increases the negative charge of the neuron making it less likely to fire and pass on the impulse

Question 19

how are signals transmitted electrically?

Answer 19

signals WITHIN neurons are transmitter electrically

Question 20

how are signals transmitted chemically?

Answer 20

signals BETWEEN neurons are transmitted chemically across the synapse

Question 21

what is summation?

Answer 21

is the process that determines whether or not an acton potential will be triggered by the combined effects off epsp and ipsp.