... We Learned About Osmosis Today!

In Biology, we are currently in our Cells unit. We have learned about the different parts of the cell and have spent the past several days learning about cell transport, primarily diffusion and osmosis. 

In high school, I remember doing an osmosis lab using an egg and perhaps at one point also some dialysis tubing. I remember thinking "why the heck would you soak an egg in vinegar and then in sugar?!" The connection wasn't there for me, even though I understood osmosis and diffusion. 

I knew going into this unit that I wanted to do something different. I had seen pictures and posts using gummy bears instead of eggs. I figured my 9th graders would enjoy this much more than an egg. 

On Day 1 of the lab, we did all of the setup. We took our initial mass measurements  and soaked each gummy bear in a different solution: water, 50% sucrose, or corn syrup. We made predictions about what we thought would happen, and we let our bears  sit over night. 

On Day 2, we took out the bears and measured their mass. The expressions on the students' faces when they first looked at their bears was priceless:

"WHOA! It EXPLODED!" (A bit dramatic...)
"Eww... could you even eat that?" (They were definitely not allowed to eat them...)
"I wonder if you could make jello like this." (This comment was so random, I had to laugh)

The bears were pretty awesome looking, even I was impressed. They were able to get their measurements easily and clean up was a breeze since I opted for disposable cups and weigh boats to avoid the sticky mess of 200+ cups. 

I think that this lab really helped them to visualize what happens in a hypotonic solution since many of them saw their bears expand so far that they burst. It took some coaxing to get them to verbalize the connections, but I was very impressed with how quickly they picked up on what was happening in the lab! 

I posted the lab -- along with teacher setup and notes -- on my TpT site! Hopefully your students enjoy it as much as I did!