{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

BIO188_Outline_Nov4

BIO188_Outline_Nov4 - B IO 188 November 4 2009 For exam...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
BIO 188 November 4, 2009 BIO 188 November 4, 2009 For exam Monday 1. bring ASU ID card 2. don’t need to memorize Nernst equation, but need to know what it means and how to use it 1. can bring calculator for comfort, but probably won’t need it Today: 3. resting membrane potential 1. generating and understanding Vm rest 2. equilibrium potential for K + 4. Nernst equation 5. excitable cells (begin action potential)
Background image of page 1

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

View Full Document Right Arrow Icon
How do we generate a resting membrane potential? 6. Resting Vm is electrical potential across plasma membrane of cell that is not “excited” (no rapid Vm) 7. Involves 2 factors: 1. 1) .. permeability of plasma membrane to k + 1. membranes of resting cells are permeable to K + 2. K + efflux via passive K efflux via passive K + leak channels is most important contributor to resting Vm leak channels is most important contributor to resting Vm 3. Na + flux also contributes But why does K+ move out of cell, leaving negative charge on inside of plasma membrane? But why does K+ move out of cell, leaving negative charge on inside of plasma membrane? What’s other factor is required to generate and maintain ( ) resting Vm? What’s other factor is required to generate and maintain ( ) resting Vm? 8. .. ; Large chemical gradient for k+ and (and NA+) across plasma membrane. 1. [K + ] much higher inside cell than outside cell 2. [K + ] in = 150 mM; [K + ] out = 5 mM 3. given the chance, K + diffuses down [gradient] What generates K+ concentration gradient? 9. This is a job for Na+ / K+ ATPase Na+ / K+ ATPase 1. a transporter transporter that uses energy of ATP hydrolysis to “pump” ions (K + and Na + ) across plasma membrane against against their concentration gradients 2. primary active transport
Background image of page 2
3. generates and
Background image of page 3

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

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}