Lecture 3

Question 1

What ions have a higher concentration inside the cell?

Answer 1

K

Potassium ions

Question 2

What ions have a higher concentration in the outside of the cell?

Answer 2

Na, Ca, Cl

Sodium, Calcium, Chloride ions

Question 3

What are the different channels?

Answer 3

non gated channel, gated channel

Channels that do not require a stimulus to open vs. channels that require a stimulus to open

Question 4

What are the different stimulus to open gated channels?

Answer 4

voltage, chemical, mechanical, temperature

Voltage changes, chemical signals, mechanical force, temperature changes

Question 5

How do the ions move once channels are open?

Answer 5

diffusion

Movement from high concentration to low concentration

Question 6

What charge is a resting membrane potential?

Answer 6

(-70)

Negative seventy millivolts

Question 7

How is the resting membrane potential maintained?

Answer 7

by active Na K pumps

Sodium-Potassium pumps actively transport ions to maintain resting potential

Question 8

What is a graded potential?

Answer 8

membrane potential changes due to ion channels opening and can reach threshold for action potential

Small changes in membrane potential that can lead to action potential

Question 9

Do all graded potentials reach action potential?

Answer 9

no, some hyperpolarize the cell body/ dendrites or are not very strong

Not all graded potentials lead to action potential

Question 10

Can graded potentials piggy back off one another?

Answer 10

yes but it does not mean that the action potential will be greater. All action potentials are the same intensity

Graded potentials can summate but action potentials remain consistent in intensity

Question 11

Where does the action potential begin?

Answer 11

trigger zone

Area where action potential is initiated

Question 12

Where do action potentials occur?

Answer 12

axon hillock to axon

From the initial segment to the axon

Question 13

What type of gates do graded potentials use?

Answer 13

Chemical, mechanical, temp, voltage

Chemical, mechanical, and temperature-sensitive gates

Question 14

What type of gates do action potentials use?

Answer 14

Voltage

Voltage-gated channels

Question 15

What fiber diameter travels faster: thin or thick?

Answer 15

thick

Thick fibers

Question 16

What is the myelinated fibers conduction called?

Answer 16

saltatory conduction

Rapid conduction in myelinated fibers

Question 17

What are the exposed axon areas between myelinated fibers called?

Answer 17

nodes of ranvier

Gaps in the myelin sheath

Question 18

What is the neural junction?

Answer 18

between the pre and post synaptic neuron

Area where neurons communicate

Question 19

What ion triggered the release of neurotransmitters by exocytosis?

Answer 19

Ca

Calcium ions

Question 20

The binding of neurotransmitters from the pre synaptic neuron triggers what type of channels to open on the post synaptic neurons?

Answer 20

chemical gated channels and helps reach action potential

Channels that open in response to neurotransmitter binding

Question 21

What neurotransmitters hyperpolarize the membrane?

Answer 21

gaba, glycine

Inhibitory neurotransmitters

Question 22

Where can receptors be found?

Answer 22

dendrites unipolar or on cells that synapse with neurons

Receptors on dendrites or synapsing cells

Question 23

What are phasic vs tonic receptors?

Answer 23

adapts to a stimuli ( clothes) vs. A continuous action potential response for the stimulus (posture)

Receptors that adapt to stimuli vs. receptors that maintain a response

Question 24

Explain the 3 order neuron sensory pathway

Answer 24

the first neuron detects the signal and sends up the spinal cord to the medulla -> the second occurs in the medulla to the thalamus -> the third goes from the thalamus to the cerebral cortex area associated with the signal

Pathway of sensory information processing