1. Grow the Gradient! Score Card
After each Filtrate Pump step and Membrane Transport step, record your interstitial and filtrate osmolarities.
Also record the gradient in the interstitial fluid following each Membrane Transport step.
After Step 1: Filtrate Pump
Step 2: Membrane Transport Calculations
After Step 2: Membrane Transport
a. Average each interstitial and ascending filtrate pair
b. New interstitial concentration = average + 100
c. New ascending filtrate concentration = average - 100
Round 1
Interstitial fluid gradient: ____
Grow the Gradient: An interactive countercurrent multiplier game
Jessica R. Santangelo and Peter Daniel
After Step 1: Filtrate Pump
Step 2: Membrane Transport Calculations
After Step 2: Membrane Transport
a. Average each interstitial and ascending filtrate pair
b. New interstitial concentration = average + 100
c. New ascending filtrate concentration = average - 100
Round 2
Interstitial fluid gradient: ____

2. Grow the Gradient! Score Card
After each Filtrate Pump step and Membrane Transport step, record your interstitial and filtrate osmolarities.
Also record the gradient in the interstitial fluid following each Membrane Transport step.
After Step 1: Filtrate Pump
Step 2: Membrane Transport Calculations
After Step 2: Membrane Transport
a. Average each interstitial and ascending filtrate pair
b. New interstitial concentration = average + 100
c. New ascending filtrate concentration = average - 100
Round 3
Interstitial fluid gradient: ____

3. Grow the Gradient! Score Card for Additional Rounds
After Step 1: Filtrate Pump
Step 2: Membrane Transport Calculations
After Step 2: Membrane Transport
a. Average each interstitial and ascending filtrate pair
b. New interstitial concentration = average + 100
c. New ascending filtrate concentration = average - 100
Round ___
Interstitial fluid gradient: ____
After Step 1: Filtrate Pump
Step 2: Membrane Transport Calculations
After Step 2: Membrane Transport
a. Average each interstitial and ascending filtrate pair
b. New interstitial concentration = average + 100
c. New ascending filtrate concentration = average - 100
Round ___
Interstitial fluid gradient: ____