Multi-celled organisms, like dolphins, are made up of trillions of cells. How do you think they work together to move an organism? How do the cells of a tree allow it to absorb water and produce leaves? How are the cells interacting with the world inside of the body and outside of the body? Do small one-celled organisms function the same way as the cells in big organisms like dolphins? We need to know how cells function, so we can understand how entire organisms, both large and small, function.
Image copyright Krzysztof Odziomek, 2014. www.shutterstock.com. Used under license from Shutterstock.com.