structure and action of neuron

Question 1

Action Potentials- is very step by step.

Answer 1

1. Na+= sodium
   Cl-= chloride
   K+= potassium.
   Action potential= neuron fired. action potential is caused by changes in the flow of charged molecules (ions) accross the neurons membrane. The term ‘action potential’ refers to the rapid change in the membrane potential of the neuron caused by movements in ions.

Question 2

Polarised

Answer 2

at rest, the membrane potential of the neuron is polarised (-70 mV.)

Question 3

depolarizes

Answer 3

As positive ions flow into cell membrane potential depolarises and moves up to 0mv. if the membrane reaches -50 mv it triggers the action potential.

Question 4

hyperpolarised

Answer 4

after one action potential passes, it takes time for the neuron to fire again, or requires a more significant change in the neuron to trigger the action potential.

Question 5

K + and Na+ channels

Answer 5

NA+ ions enter the cell, Na+ enters the cell (step 1). The K+ channels open, and the Potassium leaves the cell (step 2/depolarize) . When the sodium levels peak, (40+ mv), the channels become ‘refractory’ (step 3). K=+ continues to leave the cell, causing the membrane potential to return to resting level (step 4).

Question 6

action potential

Answer 6

primary way the electrical signal inside the neuron is propagated.

Question 7

Rate law of action potentials.

Answer 7

• neuron firing is an ‘all or none’ event, because it fires or it doesn’t.
  The neuron

Question 8

rate of law of action potentials

Answer 8

weak stimulus= slower threshold of activation= less frequent action potentials.

strong stimulus= faster threshold of activation= more frequent action potentials .

Question 9

neurotransmitters

Answer 9

chemicals synthesized within the brain/ neurons and are often called ‘chemical messages.’.

Question 10

neural excitation

Answer 10

excitatory postsynaptic potentials depolarize the post synaptic cell membrane. this increases the likelihood that an action will be triggered in the post synaptic neuron.
- GLUTAMATE

Question 11

neural inhibition

Answer 11

inhibitory post synaptic potentials= hyperpolarize the post synaptic cell membrane.
ISPS decrease the likelihood that an action potential will be triggered.
- GABA

Question 12

neural integration

Answer 12

each neuron receives input from many other neurons, the neuron will fire if the sum of excitatory inputs is sufficiently greater than the inhibitory inputs.

Question 13

neurotransmitter process

Answer 13

NT will bind to the receptor (lock and key) and trigger change to the ion channel, which will allow for ions to flow through.

Question 14

action of drugs at receptors

Answer 14

• drugs work by mimicking the chemical structure of the natural compound. (They will block of inc likelihood of firing)
• agonist or antagonist