Biological Science (6th Edition)
Biological Science (6th Edition)
6th Edition
ISBN: 9780321976499
Author: Scott Freeman, Kim Quillin, Lizabeth Allison, Michael Black, Emily Taylor, Greg Podgorski, Jeff Carmichael
Publisher: PEARSON
bartleby

Concept explainers

bartleby

Videos

Question
Book Icon
Chapter 43, Problem 1TYK
Summary Introduction

Introduction:

The pore-forming membrane proteins are referred to as ion channels, which permit the ions to cross the channel pore. Their main functions include establishing a resting membrane potential and shaping action potentials and other signals by allowing the flow of ions across the membrane.

Expert Solution & Answer
Check Mark

Answer to Problem 1TYK

Correct answer:

The neurons have a significantly larger number of potassium leak channels, which facilitate the leakage of potassium ion across the membrane.

Explanation of Solution

Explanation/Justification for the correct answer:

Option (b) is given as potassium ion (K+). K+ is a micronutrient that is required by almost all cell types and is also necessary for the maintenance of the electrolyte and fluid balance in the body. The sodium–potassium pump creates the potassium gradient across the cell, with the higher concentration of potassium inside the cell. Thus, the K+ ions move from a higher concentration region to a lower concentration region, in turn generating an action potential. Furthermore, this helps in achieving the negative resting potential of the cell. Hence, option (b) is correct.

Explanation for incorrect answers:

Option (a) is given as calcium ions (Ca2+). The leakage of Ca2+ ions does not occur in order to achieve the resting potential as the concentration gradient for Ca2+ ions is not created by the sodium–potassium pump. So, it is a wrong answer.

Option (c) is given as sodium ions (Na+). The number of leak channels for Na+ ions is comparatively less than that for potassium ions. So, it is a wrong answer.

Option (d) is given as chloride ions (Cl+). The chloride ions are present as Cl and not as Cl+. So, it is a wrong answer.

Hence, options (a), (c), and (d) are incorrect.

Conclusion

Therefore, it can be concluded that the potassium ions leak across the neuron’s membrane and thereby accomplish the resting potential.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
After the depolarisation phase of an action potential, the resting potential is restored by ______.   Question 15 options:   A)  the opening of voltage-gated potassium channels and the closing or inactivation of sodium channels.   B)  the opening of more voltage-gated sodium channels.   C)  a decrease in the membrane's permeability to potassium and chloride ions following closing of the chloride-potassium pump.   D)  a brief inhibition of the sodium-potassium pump.
The presence of an electrical gradient is responsible for both the resting membrane potential and the action potential in the neuron.a. In this case who is responsible for maintaining the electric gradient to produce a potential for the resting membrane?b. Explain what is meant by an electrical gradient in the context of a cell (neuron)!
a) How does E allow faster transmission of signals?  b) What would happen if G has a lack of Calcium? c) Most neurons have the style of junction (chemical) shown in the diagram, rather than gap (electrical) junctions. Why does this make sense?
Knowledge Booster
Background pattern image
Biology
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
  • Text book image
    Concepts of Biology
    Biology
    ISBN:9781938168116
    Author:Samantha Fowler, Rebecca Roush, James Wise
    Publisher:OpenStax College
Text book image
Concepts of Biology
Biology
ISBN:9781938168116
Author:Samantha Fowler, Rebecca Roush, James Wise
Publisher:OpenStax College
The Cell Membrane; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=AsffT7XIXbA;License: Standard youtube license