Neuron function worksheet with complete solution

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euron function worksheet with complete solution what is the job of a neuron Correct Answer- to move an electrical signal from one place to another in order to send sensory messages throughout the body... Which of the gated embedded proteins in Model 1 allow sodium ions ( O ) through the membrane? Correct Answer- gates A, B, D and F allow sodium ions through the membrane Which of the gated embedded proteins in Model 1 allow potassium ions ( triangles ) through the membrane? Correct Answer- Gates C, E, and G allow potassium ions through the membrane The neuron illustrated in Model 1 has received a signal from either a sensory cell (taste bud, skin cell, retinal cell, etc.) or from another neuron. What evidence do you find in diagram 1 of the model that indicates a signal has been received? Correct Answer- A signal Ligand has bound to the ligand-gated embedded protein and the gate has opened In diagram 2 of Model 1, gated embedded protein B has opened. Was this opening triggered by the arrival of a signal ligand? If no, propose an alternate stimulus that might have triggered the gate to open. Correct Answer- No, diagram 2 does not show a ligand bound to embedded protein B. The gate may have opened because of the change in membrane potential from the flood of ions nearby When a signal moves down the axon of the neuron, which direction sodium ions move through the voltage-gated embedded proteins? Correct Answer- sodium ions move into the cell when the sodium gates are opened What does the movement of sodium ions across the membrane do to the membrane potential near the open embedded protein? Correct Answer- the membrane potential increases (gets more positive) as the sodium ions move into the cell When a signal moves through the axon of the neuron, which direction do potassium ions move through the voltage-gated embedded proteins? Correct Answer- potassium ions move out of the cell when the potassium gates are opened What does the movement of potassium ions across the membrane do to the membrane potential near the open embedded protein? Correct Answer- the membrane potential decreases ( gets more negative) as the potassium ions move out of the cell when a neuron is resting the cell membrane is said to be POLARIZED Correct Answer- how is the degree of polarization measured? Correct Answer- the degree of polarization is measured by the cell membrane potential the gated embedded proteins in the axon of a neuron are triggered to open by changes in electrical potential across the membrane. Correct Answer- the voltage at which they open is called the threshold potential Looking at model 1 What is the threshold potential that causes the sodium ion gates to open? Correct Answer- the sodium ion gates open at -55 mV Looking at model 1 At what potential are the potassium ion gates fully open? Correct Answer- the potassium ion gate open at +35 mV looking at model 1 at what potential are the sodium ion gates closed Correct Answer- the sodium ion gates close when the membrane potential reaches +35 mV At what potential are the potassium ion gates closed? Correct Answer- The potassium ion gates close when the membrane potential reaches -80 mV Describe how the electrical signal in the neuron moves Correct Answer- the gates open one at a time from left to right in model 1. the high concentration of sodium ions inside the cell moves from left to right in model 1 A. When the gated embedded proteins (either sodium or potassium) close, do the sodium and potassium ions remain on the side of the membrane that they are on, or do they move back to their original position? Correct Answer- The sodium and potassium ions eventually move back to their original position B. Propose a mechanism that the cell might use to accomplish the change you describe in part A Correct Answer- The sodium and potassium ions move through embedded proteins in the membrane to reinstate the resting membrane potential C. Could another signal be sent down the length of the neuron cell if the sodium ions and potassium ions were not returned to their original position? Correct Answer- No, the neuron cannot transmit another signal until the ions are returned because the concentration gradients for the ions are going in the wrong direction Define depolarized Correct Answer- When an action potential is in progress the cell membrane is depolarized. The potential difference between the two sides of the membrane is decreased Define refractory period Correct Answer- After a sodium ion gate has been opened and closed it is in a refractory period where the membrane potential in the immediate vicinity is very low and the embedded protein cannot be opened again. This is called hyperpolarizaton and and repolarization define hyperpolarization Correct Answer- hyper means beyond normal. Hyperpolarization means there is a difference in membrane potential that is GREATER than normal Define repolarization Correct Answer- Occurs immediately after depolarization and is the movement of positively charged ions back to the outside of the cell, returning the cell back to its original polarized state. A cell must repolarize before it can depolarize again. define polarization Correct Answer- polarization refers to the difference in potential on either side of the membrane according to model 1 ,what is the membrane potential near sodium ion gates during the refractory period ? Correct Answer- the lowest potential in model 1 is -80mv nerve [Show More]

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