4-neurotransmitters

Question 1

Define neurotransmitters ?

Answer 1

Chemical substance transmit activity through synapses

Question 2

classified ?

Answer 2

Chemical structure & rapidity of action

Question 3

Rapid acting transmitters act by ?

Answer 3

Activation of ion channels

Question 4

Rapid acting transmitters responsible for ? (2)

Answer 4

Transmission of
- sensory impulse to brain
- motor signals to muscle

Question 5

Rapid acting transmitters synthesized in ?

Answer 5

Presynaptic terminals

Question 6

Rapid acting transmitters stored in ?

Answer 6

Transmitters vesicles

Question 7

Rapid acting transmitters released in?

Answer 7

Large quantities

Question 8

Rapid acting transmitters removed by (2) ?

Answer 8

Active reuptake
Enzymatic destruction

Question 9

Rapid acting transmitters class 1 ? (1)

Answer 9

Acetylcholine

Question 10

Rapid acting transmitters class 2 amines (5) ?

Answer 10

• norepinephrine
• epinephrine
  -dopamine
• serotonin
• histamine

Question 11

Rapid acting transmitters class 3 a.as ?(4)

Answer 11

• GABA
• glycine
  -glutamate
  -aspartate

Question 12

Rapid acting transmitters class 4 ? (1)

Answer 12

Nitric oxide

Question 13

Neuropeptides act by ?

Answer 13

2nd messenger

Question 14

Neuropeptide synthesized in ————-?
Released in ———quantity & —————?

Answer 14

• by neurons
  Small quantity but more potent

Question 15

Neuropeptide synthesized by ———- in ————-?

Answer 15

Ribosomes in neural cell body

Question 16

Neuropeptide synthesis in steps (3) ?

Answer 16

1- ribosomes
2- enter golgi appartus ( split & packed )
3 - transported to tip of nerve fibers by axonal streaming

Question 17

Properties of synaptic transmission ?

Answer 17

1) unidirectional conduction
2) synaptic delay
3) synaptic fatigue
4 ) change in composition of ECF
5) effect of drug

Question 18

Unidirectional conduction is ?

Answer 18

Impulse only conducted from presynaptic to post synaptic

Question 19

Unidirectional conduction prevent ?

Answer 19

Anti-dromic impulse

Question 20

Synaptic delay is ?

Answer 20

The time needed for conduction of impulse (0.5m.sec )

Question 21

In synaptic delay Time is needed for?

Answer 21

1- release of transmitters
2- diffuse through synaptic cleft
3- combination with postsynaptic receptor
4- Na influx = EPSP
5- summation of EPSP

Question 22

synaptic delay can be used to know ?

Answer 22

Number of synapses

Question 23

Synaptic fatigue is?

Answer 23

when presynaptic neuron is stimulated repettied at rapid rate, discharge from postsynaptic will gradually decrease.

Question 24

Synaptic fatigue is due ?

Answer 24

Rate of release of neurotransmitters > grater than rate of reformation

Question 25

Synaptic fatigue is protective mechanism how ?

Answer 25

In people with epileptic shock stops it after 2-3 min

Question 26

Inhibitory condition? (4)

Answer 26

• acidosis = coma
• hypoxia
• hypoglycemia
  -hypocalcemia

Question 27

Inhibitory drugs ?

Answer 27

Anesthetics & sedative (inc threshold to stimuli )

Question 28

Excitatory conduction?(3)

Answer 28

• alkalosis = convulsion
• hypercalcemia
• hyperthyroidism

Question 29

excitatory drugs?

Answer 29

• xanthines
• strychnine