1 / 12

TRANSPORT ACROSS MEMBRANES

TRANSPORT ACROSS MEMBRANES. THE WAY CELLS REGULATE THEIR CONTENTS. TWO MAJOR TYPES OF TRANSPORT. PASSIVE: Only from high concentration to low ACTIVE: Can actually pump up a gradient using energy from some other source such as ATP (Primary) or another gradient (Secondary). Passive Transport.

lea
Télécharger la présentation

TRANSPORT ACROSS MEMBRANES

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. TRANSPORT ACROSS MEMBRANES THE WAY CELLS REGULATE THEIR CONTENTS

  2. TWO MAJOR TYPES OF TRANSPORT • PASSIVE: Only from high concentration to low • ACTIVE: Can actually pump up a gradient using energy from some other source such as ATP (Primary) or another gradient (Secondary)

  3. Passive Transport • Diffusion • Bulk Flow • Electrodiffusion • Current Flow • Osmosis • Facilitated Diffusion

  4. Diffusion Before: • Diffusion occurs when concentration in one region is greater than in another • The end result is an even distribution called equilibrium After:

  5. Diffusion across a permeable membrane Before: • Diffusion occurs when concentration in one region is greater than in another • The end result is an even distribution called equilibrium After:

  6. Impermeable membrane Before: • Diffusion can not occur After:

  7. Bulk Flow • Analogous to the flow of water through a pipe • Through pores in membranes • Through blood vessels • Through other tubular structures

  8. - Current Flow POSITIVE REGION NEGATIVE REGION + CATIONS AND ANIONS MOVE IN OPPOSITE DIRECTIONS CARRYING ELECTRICAL CURRENT CURRENT = FLOW OF CATIONS - FLOW OF ANIONS

  9. SOLUTE NO SOLUTE Osmosis Water moves across a semi-permeable membrane to the side where the solute is most concentrated After: Before: SOLUTE NO SOLUTE

  10. Facilitated Diffusion • 1. Molecule binds to carrier • 2. Carrier changes conformation • 3. Molecule released on other side • 4. Purely passive process- stops when concentrations are equal

  11. ACTIVE TRANSPORT REQUIRES AN INPUT OF ENERGY • USUALLY IN THE FORM OF ATP • ATPase IS INVOLVED • SOME ASYMMETRY IS NECESSARY • CAN PUMP UPHILL

  12. ACTIVE TRANSPORT ADP ATP

More Related