Lecture 23 - BIOL104-04 Principles of Biology I October 21,...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
BIOL104-04 Principles of Biology I October 21, 2010 Lecture #23 Ch 51 Osmotic Regulation & the Urinary System
Background image of page 1

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

View Full DocumentRight Arrow Icon
Vertebrate Nephron
Background image of page 2
Proximal tubule Site of reabsorption Active transport of selected molecules out of the pre- urine Epithelium has many microvilli Increased surface area for membrane proteins – Pumps – Channels – Cotransporters (Symporter) Lots of mitochondria – Processes require ATP
Background image of page 3

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

View Full DocumentRight Arrow Icon
Mechanisms of selective reabsorption Basolateral Na + /K + ATPase removes Na + from interior of cell to create a gradient Na + can then enter cell via cotransporters from pre- urine in lumen Movement of Na + along gradient allows other solutes to be brought into cells against gradient Chloride follows passively due to electrochemical interactions Water follows the solutes via osmosis
Background image of page 4
Background image of page 5

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

View Full DocumentRight Arrow Icon
Background image of page 6
Aquaporins • Membrane proteins • Water channels • 3 billion water molecules transfer/second • Found in membrane of epithelial cells • Facilitate the movement of water
Background image of page 7

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

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 20

Lecture 23 - BIOL104-04 Principles of Biology I October 21,...

This preview shows document pages 1 - 8. Sign up to view the full document.

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