Chapter 5

Question 1

Polarized

Answer 1

Under normal circumstance any time we are not at zero we are polarized

Question 2

Resting membrane potential

Answer 2

Where we are normal set at
For a neuron -70

Question 3

How do we stay at -70

Answer 3

Proportionate Ion Flux

Question 4

Proportionate Ion Flux

Answer 4

Maintains steady state

Question 5

Steady State is deviated

Answer 5

Deviation in membrane potential results from disproportionate ion flux

Question 6

Depolarization

Answer 6

Leaving the polar state and going back toward zero
-leaving the resting state

Question 7

Going past zero still going up

Answer 7

Depolarization

Question 8

Going back to a polar condition from zero

Answer 8

Repolarization

Question 9

Going lower past the polar state

Answer 9

Hyperpolarization

Question 10

What is the importance of Ion Flux and membrane potential?

Answer 10

Ion flux and membrane potential plays an important role in cellular and organismal function. Changes in Vm cause cellular responses in excitable and non-excitable tissues.

Question 11

Beta Cella of pancrease

Answer 11

Produce and secrete insulin

Question 12

Role of insulin

Answer 12

Required by most cells to absorb glucose from the plasma

Question 13

How can beta cells monitor low blood glucose concentrations?

Answer 13

 Have a beta cell next to the blood stream
 Currently have low glucose amounts
 Beta cell is trying to take in glucose by a carrier
 Don’t have a high concentration
 Don’t have a high glucose influx
 Glucose is not coming in and unable to break it down
 Not going to have much of a metabolism
 Decreases ATP cells are barley getting by
 Have a leak channel with potassium flowing out of the cell
 Cell is less positive
 Hard to depolarize the cell
 Nothing is going to happen
 Voltage-gated Ca++ channel closed
 No insulin is going to be released
 There is no drive for it to be released

Question 14

How can beta cells monitor high blood glucose concentrations?

Answer 14

 Have beta cell next to blood stream
 High glucose amounts
 Have a high gradient for glucose
 Going to come into the cell through the carrier
 Glucose is getting broken down
 Metabolism increases
 ATP increases
 Potassium ATP Leak channel is closed
* Potassium cannot leave
 Positive charges can no longer leave
 Easier to depolarize
 Depolarizes the membrane
 Inside of cell more positive and change in membrane potential
 Voltage-Gated calcium channels open
 Calcium will flood into the cell
 Making the cell even more positive
 Depolarizing it even more
 Ca++ entry acts as an intracellular signal
 Ca++ signal triggers exocytosis, and insulin is secreted
 Insulin is in the blood stream at a high concentration and will find cells that need insulin, and tell those cells to take in glucose
 Those cells take in glucose and blood glucose levels are being lowered

Question 15

What is high glucose levels in blood being regulated an example of

Answer 15

Negative Feedback Loop