Tubular reabsorption sodium and water reabsorption
This presentation is the property of its rightful owner.
Sponsored Links
1 / 10

Tubular Reabsorption , Sodium and Water Reabsorption PowerPoint PPT Presentation


  • 80 Views
  • Uploaded on
  • Presentation posted in: General

Tubular Reabsorption , Sodium and Water Reabsorption. Created by David Sunwoo, not Joy Kim, F Block. Tubular Reabsorption. The process by which filtered substances are returned to the bloodstream.

Download Presentation

Tubular Reabsorption , Sodium and Water Reabsorption

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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Tubular reabsorption sodium and water reabsorption

Tubular Reabsorption, Sodium and Water Reabsorption

Created by David Sunwoo, not Joy Kim, F Block


Tubular reabsorption

Tubular Reabsorption

  • The process by which filtered substances are returned to the bloodstream.

  • Transported out of the tubular fluid -> through the epithelium of the renal tubule -> interstitial fluid -> substance diffuses into the peritubular capillaries -> internal environment

  • In this process, substances must first cross the cell membrane facing the interstitial fluid.


Tubular reabsorption cont

Tubular Reabsorption cont..

  • Tubular reabsorption mainly takes place in the proximal convoluted portion.

  • Microvilli is microscopic projects that form a “brush border” on the epithelial cell’s surface.

    • Also greatly increases the surface area exposed to glomerular filtrate

    • Enhances reabsorption


Active transport

Active Transport

  • Reabsorbs glucose through the walls of the proximal convoluted tubule

  • Utilizes carrier molecules in cell membranes

    • These carriers transport certain molecules across the membrane release them and the repeat the process

    • But has limited transport capacity – can only transport a certain number of molecules in a given time because the number of carriers is limited


Tubular reabsorption cont1

Tubular Reabsorption cont..

  • Some glucose remains in the tubular fluid because of the renal plasma threshold (when the plasma glucose concentration increases to a critical level)

  • Amino acids enter the glomerular filtrate (nearly free of protein) and are reabsorbed in the proximal convoluted tubule leaving only a trace of amino acids

  • Lastly, the epithelium of the proximal convoluted tubule reabsorbs other substances


Sodium and water reabsorption

Sodium and Water Reabsorption

  • Water reabsorption occurs passively by osmosis in the proximal convoluted tubule

  • Active transport reabsorbs most of the sodium ions in the proximal segment of the renal tubule

    • Negatively charged ions move during active transport through a form of passive transport

  • As active transport occurs, the concentration of solutes within the peritubular blood increases.


Sodium and water reabsorption1

Sodium and Water Reabsorption

  • Water moves by osmosis from the renal tubule -> peritubular capillary

  • Movement of solutes and water = reduction of fluid volume within the renal tubule

  • In conclusion, almost all the sodium ions and water that enter the renal tubule as part of the glomerular filtrate are reabsorbed before urine is excreted.


Review questions

Review Questions

  • 1. How does water move from the renal tubule into the peritubular capillary?

  • 2. What are microvilli and what are their functions?

  • 3. What’s active transport’s main job in sodium and water reabsorption?

  • 4. What is renal plasma threshold?

  • 5. Where does tubular reabsorption mainly take place in?


  • Login