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Knoxville — Inside a second-floor biology lab in Hesler Hall at the University of Tennessee, Knoxville, sophomore Hannah Barry peers through a microscope and carefully adjusts a water-filled slide sitting beneath the lens. She’s studying her MicroAquarium for microscopic signs of life.

Happy with the focus, Barry turns her attention to a wide-screen monitor connected to a camera looking down the microscope. Barry has identified a cyclops, a multi-celled, shrimp-like microorganism, swimming across the screen.

Hannah Barry
Hannay Barry looks for changes in the microorganisms from her water sample.

“I started with twenty of these, and now I can only find five,” Barry said. “I thought the cyclops would dominate, but so far as I can tell, they just haven’t. They’ve disappeared.”

Barry is one of ninety-six Biology 111 students studying the micro-aquatic ecosystems of Knoxville-area water samples. For this semester-long project, students must identify protists, a diverse group of microorganisms, watch what happens to those microorganisms as the aquatic environment is modified, and hone their science writing skills by describing what they see through lab reports and ongoing blogs.

In September, students filled their MicroAquarium with a water sample from a variety of water bodies, including Meads Quarry, Fountain City duck pond, the French Broad and Holston rivers, and various ponds and natural springs.

“There is a wide diversity of organisms in what the students are finding in each water source,” said class lecturer Ken McFarland. “In their lab report, they draw comparisons between the different water samples.”

After one week, students added one food pellet to each water sample, stimulating often-dramatic population increases among the different organisms.

“We are interfering with the ecosystem by adding food, but watching what goes on in an ecological sense is very interesting,” said McFarland.

“If you have a food source, you’re not limited by the amount of energy you can use. Food provides energy for reproduction,” said Barry.

As the organisms populate and algae bloom, the students document their observations in ongoing blogs.

“Writing about their findings helps the students express what they’re seeing under the lens,” McFarland explained. “It prepares the students for more advanced scientific writing in the future.”

“It’s been fun. I’m taking creative license with my blog,” Barry said. “The project has taught me about all kinds of different single- and multi-celled organisms that I will be able to identify in the future.”

Images and videos of the microorganisms in action are also posted on the blogs, providing a fascinating microscopic look into Knoxville’s aquatic ecosystems.

“Drinking water needs to be sanitized, but healthy, outside waterways aren’t always clean,” Barry said. “Rivers need a variety of organisms to be active and promote biodiversity. It stops disease from coming through and wiping everything out. Life thrives with the more organisms that are present.”

Read Hannah Barry’s blog at Read other Biology 111 blogs here. For more information on UT’s Division of Biology, visit


Ken McFarland (865.974.6841,

Lynn Champion (865.974.5332,