L3_NPB_101 - Lecture3 OnlineHandouts Lec3Notes...

Info icon This preview shows pages 1–16. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture 3 Online Handouts: Lec 3 Notes Announcements: None Reading (Recommended): Reading: Ch 4 (pp 85‐97) Membrane PotenFal The Neuron AcFon PotenFal
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Membrane PotenFal
Image of page 2
Membrane PotenFal Plasma membrane of all living cells has a membrane potenFal (polarized electrically) SeparaFon of opposite charges across plasma membrane Due to differences in concentraFon and permeability of key ions
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Unequal DistribuFon of Ions Fig. 3‐20, pg. 75
Image of page 4
Membrane PotenFal Nerve and muscle cells Excitable cells Have ability to produce rapid, transient changes in their membrane potenFal when excited ResFng membrane potenFal Constant membrane potenFal present in cells of nonexcitable Fsues and those of excitable Fssues when they are at rest
Image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Suppose a concentraFon gradient exists for K + and A Let’s make the membrane IMPERMEABLE to A K + flows out of the cell Plasma membrane ECF ICF E K + = -90 mV Fig. 3‐20, pg. 76
Image of page 6
The Equilibrium PotenFal for K + A concentraFon gradient pushes K + out of the cell An electrical gradient pulls K + back into the cell Forces balance at equilibrium Electrochemical Equilibrium E i (e.g., E K+ ) Plasma membrane ECF ICF Concentration gradient for K + Electrical gradient for K + E K + = –90 mV Fig. 3‐20, pg. 76
Image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Equilibrium PotenFal for Na + A concentraFon gradient pushes Na + into the cell An electrical gradient pulls Na + out of the cell Forces balance at equilibrium E Na+ Plasma membrane ECF ICF Concentration gradient for Na + Electrical gradient for Na + E Na + = +60 mV Fig. 3‐21, pg. 78
Image of page 8
Real Cells are Permeable to Several Ions K + flows out Na + flows in Cl flows in Plasma membrane ECF ICF Relatively large net diffusion of K + outward establishes an E K+ of –90 mV No diffusion of A– across membrane Relatively small net diffusion of Na + inward neutralizes some of the potential created by K + alone Resting membrane potential = 70 mV (A = Large intracellular anionic proteins) Fig. 3‐22, pg. 78
Image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Sodium‐Potassium Channels Fig. 3‐23, pg. 79
Image of page 10
The Neuron
Image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Model of a Mammalian Neuron Fig. 4‐10, pg. 94
Image of page 12
Neuron Basic parts of neuron (nerve cell) Cell body Dendrites Axon
Image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Neuron Cell body Houses the nucleus and organelles Dendrites Project from cell body and increase surface area available for receiving signals from other nerve cells Signal toward the cell body Dendrite and cell body serve as the neurons input zone.
Image of page 14
Neuron Axon Nerve fiber Single, elongated tubular extension that conducts acFon potenFals away from the cell body ConducFng zone of the neuron Collaterals Side branches of axon
Image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 16
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern