BuyFindarrow_forward

Biology: The Dynamic Science (Mind...

4th Edition
Peter J. Russell + 2 others
ISBN: 9781305389892

Solutions

Chapter
Section
BuyFindarrow_forward

Biology: The Dynamic Science (Mind...

4th Edition
Peter J. Russell + 2 others
ISBN: 9781305389892
Textbook Problem

The major role of the Na+/K+ pump is to:

a. cause a rapid firing of the action potential so the inside of themembrane becomes momentarily positive.

b. decrease the resting membrane potential to zero.

c. hyperpolarize the membrane above resting value.

d. cause an action potential to enter a refractory period.

e. maintain the resting membrane potential at a constantnegative value.

Summary Introduction

Introduction:

Neurons carry electric impulses to the brain. They contain Na+/K+ (sodium/ potassium) ion pumps on their membrane, which help in generating electric impulses by pumping ions like sodium and potassium, throughout the neuron membrane. In resting condition (when there is no stimulus), the electrical charge of the neuron on the inside stays negative and outside the neuron is positive. This is due to the different concentration of ions distributed on both ends of the nerve cell.

Explanation

Justification/explanation for the correct answer:

Option (e) states that the main role of Na+/K+ pumps is to maintain the resting membrane potential at a constant negative value. When neurons get excited and the action potential is generated, the inside of the neuron becomes positive as Na+ enter into the neuron through ion pumps. After action potential is generated, neurons must go back to their resting state and inside of the neuron must become negatively charged (−70 mv) as compared to the outside. This happens due to an outflow of the potassium ion from the ion pumps, which compensates with the inflow of sodium ions. Hence, the option (e) is correct.

Explanation for the incorrect answers:

Option (a) states that the main role of Na+/K+ pumps is to cause a rapid firing of the action potential, so that the inside of the membrane becomes momentarily positive. When an action potential is generated, the inside of the membrane becomes momentarily positive. This occurs due to the inflow of sodium ions from the outside of the neuron to the inside, which is known as depolarizatio, but this does not occur rapidly as it is a slow process. So, it is an incorrect option...

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Additional Science Solutions

Find more solutions based on key concepts

Show solutions add

Match each organelle with its correct function.

Human Biology (MindTap Course List)

A way to prevent spoilage of unsaturated fats and make them harder is to change their fatty acids chemically th...

Nutrition: Concepts and Controversies - Standalone book (MindTap Course List)

Express in unit-vector notation the following vectors, each of which has magnitude 17.0 cm. (a) Vector E is dir...

Physics for Scientists and Engineers, Technology Update (No access codes included)