Question

1) Answer the following questions: a) Explain a concentration gradient using K+, Na+, and Cl-. b)...

1) Answer the following questions:

a) Explain a concentration gradient using K+, Na+, and Cl-.

b) I have a nerve cell and sodium channels are blocked. What happens when potassium rushed out of the cell?

Homework Answers

Answer #1

A) The Na+/K+ Pump creates a concentration gradient by moving 3 Na+ out of the cell and 2 K+ into the cell.

the pump continues to move Na+ out of the cell even when more Na+ions are present there.   In other words, Na+ is being pumped (and K+ in) against their concentration gradients.

Because this pump is moving ions against their concentration gradients it requires energy in the form of ATP.

B) The cell will become HYPERPOLARISED. Hyperpolarization is when the membrane potential becomes more negative at a particular spot on the neuron’s membrane. This means that the interior of the cell is negatively charged relative to the outside.While hyperpolarized, the neuron is in a refractory period that lasts roughly 2 milliseconds, during which the neuron is unable to generate subsequent action potentials.

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Plot the voltage of the cell using the original parameters for Na, K and Cl, and...
Plot the voltage of the cell using the original parameters for Na, K and Cl, and changing sodium permeability from 1 to 10, 100, 1000 and up to 9999. Will the voltage keep increasing positively as the permeability to sodium is increasing? Why? Plot the voltage of the cell using the original parameters for Na, K and Cl, and changing potassium permeability from 1 to 10, 100, 1000 and up to 9999. Will the voltage keep increasing negatively as the...
4) Recall that after the Na+ channels open the K+ channels open. Again to make the...
4) Recall that after the Na+ channels open the K+ channels open. Again to make the calculations relatively simple, solve the Goldman equation again with all resting conditions EXCEPT a 100 fold increase in potassium permeability. (2 points) [Hints, first, while I always stress the importance of units, in this case the simplified equation uses lumped constants (RT/F) and thus the units are factored in – so you can, this time, ignore the units. Second, remember that Cl- is a...
1. Calculate the free energy of transport (Gt) for the movement of sodium ions (Na+ )...
1. Calculate the free energy of transport (Gt) for the movement of sodium ions (Na+ ) from the extracellular space into the cell under the following conditions: [Na+ ]out = 140 mM; [Na+ ]in = 12.0 mM;  =−60.0 mV; T = 37.0C. Use R = 8.314 J/mol K; F = 96,500 J/V mol. 2. Calculate the free energy of transport (Gt) for the movement of potassium ions (K+ ) from the extracellular space into the cell under the following...
1. At resting membrane potential in a neuron, which is true of the forces responsible for...
1. At resting membrane potential in a neuron, which is true of the forces responsible for the movement of potassium (directed into or out of the cell)? Select one: a. The chemical gradient is outward while the electrical gradient is inward b. Chemical gradient is inward while the electrical gradient is outward c. Chemical and electrical gradients are directed outward d. Chemical and electrical gradients are directed inward 2. Multiple sclerosis is a devastating disease because it... Select one: a....
Which of the following is true? a)When the neuron is in the resting state there is...
Which of the following is true? a)When the neuron is in the resting state there is no potential across the membrane. b)The concentration of Na+ is higher inside the nerve cell than outside the cell in the resting state. c)Na+ and K+ ions move into and out of the nerve cell by diffusion across the membrane. d)Negatively charged proteins move from outside the nerve cell to the inside to help establish a negative potential gradient in the resting neuron. e)Curare...
Neurology questions: Membrane potentials Answer the 3 following 1- In an experiment about the action potential,...
Neurology questions: Membrane potentials Answer the 3 following 1- In an experiment about the action potential, what kind of effect does changing Ek to a more negative value (-95) has on the action potential? a) The inflection point was observed too early b) The peak of the graph decreased c) The lowest point of the graph (undershoot) turned more negative d) The threshold decreased Explain your answer: 2- Under what conditions would Ek be more positive? a) The internal concentration...
5) A new drug has been discovered that completely opens the voltage-gated potassium channels. If this...
5) A new drug has been discovered that completely opens the voltage-gated potassium channels. If this drug is used experimentally on an isolated axon, the membrane potential can be easily measured. Assume that this experiment provided the following results. The extracellular Na+ is 145 mM and the extracellular K+ is 4mM, the measured membrane potential in the presence of the drug is -94mV. Using this information, calculate the intracellular K+ concentration. To solve this equation, you will need to use...
1. Skeletal Muscle Shortening would decrease the length of all of the following except the: A....
1. Skeletal Muscle Shortening would decrease the length of all of the following except the: A. H-band B. Sarcomere C. A-Band D. I-Band 2. All of the following ions have a higher extracellular concentration than intracellular concentration about: A. Sodium B. Chloride C. Calcium D. Potassium 3. If the concentration of an ion equal in the extracellular & intracellular space of a nerve cell, the equilibirum (Nermst) potential for that ion is: A.+60mV B. Cannot determine from the information provided...
2. Under physiological conditions, the Na+-K+ pump transports sodium and potassium across the membrane through the...
2. Under physiological conditions, the Na+-K+ pump transports sodium and potassium across the membrane through the hydrolysis of ATP. This occurs in a sequence of steps. A. (5pts) Beginning with the START step, put the other steps a-e (currently listed in random order) of the Na+-K+ pump’s mechanism in order to complete a full cycle of transport. START – The protein is phosphorylated open to the extracellular side, and contains 2 K+ ions. a. ATP hydrolysis, protein phosphorylation, and ADP...
Answer the following questions for a reaction whose rate law is: rate = k[A][B] What is...
Answer the following questions for a reaction whose rate law is: rate = k[A][B] What is the overall order of the reaction? Select one: a. first b. second c. Third If the concentration of both A and B are doubled, how will this affect the rate of reaction? Select one: a. no change b. rate increases by a factor of 2 c. rate increases by a factor of 4 d. rate increases by a factor of 8second c. third