Proteins and Pineapples

This week in Sisters4Science at Reavis, we learned about proteins and proteases with our guest scientist, Erin!

Erin brought water, jello mix, canned pineapples, and fresh pineapples. Each girl got three test tubes–one to put fresh pineapples in, one to put canned pineapples in, and one to leave empty. Then, we each used a pipette (something that measures liquid) to transfer the water and jello mix to our test tubes.
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We learned that jello is made of gelatin, which is a protein. Some types of proteins, especially the ones in pineapples, are called proteases–which are proteins that cut up other proteins. With this information, we made a hypothesis: Kemonte and Jasaande thought that the canned pineapple had more protease, and Alita and Aaliyah thought the fresh pineapple had more protease. We agreed that if the pineapple has protease, then the proteins in the jello will be cut up, so it won’t set properly and it’ll still be a liquid instead of a solid.
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Erin taught us all about animal cells, and where proteins fit into the structure of life (from community to organism to tissue to cells to organelles to proteins!). Aaliyah asked some really great questions about the structure of a cell, and Jasaande shared with us what she knew about the difference between plant and animal cells. Then, Alita informed us all about her knowledge of sickle cell anemia and how it affects red blood cells, and Erin explained to us how it works, while Kemonte kept the timer to make sure we would take out our experiment and see the results at the right time.
In the end, we saw that the test tubes with no pineapple and with canned pineapple had solid jello, but the one with fresh pineapple was still a liquid! Erin explained to us that, when pineapples are canned, they get heated to kill bacteria, and the heat ruins the proteases so they won’t be able to work. That’s why canned pineapple reacted like no pineapple–but fresh pineapple still had proteases, so the gelatin was all cut up and couldn’t turn into a solid!
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Because of their great contributions in the session, asking relevant questions, and sharing their information, all of the girls earned their Communication Badges. Great job, Sisters!