Lecture_7_Jan_20_

Lecture_7_Jan_20_ - Five General Considerations for...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Five General Considerations for Membrane Transport Whether is energy required for a transport process? If energy is not needed, whether is a protein needed? If energy is needed (a protein is also needed in this case), what is the source of energy? ions are moved across the membrane how to maintain the If ions are moved across the membrane, how to maintain the electrical neutrality (and ionic conc) of a cell or compartment? If H + or OH - are moved across the membrane, how to maintain the pH of a cell or compartment?
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
2 Acidification of the Stomach Lumen by Parietal Cells Parietal cells are a type of epithelial cells responsible for the acidification of stomach lumen i t l l l Parietal cell ve players involved in the acidification of lumen: five players involved in the acidification of lumen: one enzyme: carbonic anhydrase two transporters: one H + /K + ATPase and one Cl - /HCO3 - antiporter two channels: one K + channel and one Cl - channel
Background image of page 2
3 The acidification of stomach lumen is achieved by H + /K + ATPase. The H + /K + ATPase uses the energy of ATP to pump H + from the parietal cell into the lumen and K + from the lumen into the parietal cells against their unfavorable ECG. This transport process itself is OK from the energy and electrical points of view, but why are the other players needed then?
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
4 Potential problems caused by the transport mediated via H + /K + ATPase. arietal cell Parietal cell For each transport cycle mediated by H + /K + ATPase, one OH - is accumulated inside the
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 18

Lecture_7_Jan_20_ - Five General Considerations for...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online