A eukaryote is any cell or organism that possesses a clearly defined nucleus. Eukaryotic cells form the foundation of complex, multicellular life, including apple trees, mushrooms, fish and humans.

A structure is an object made from many parts. Buildings and bridges are examples of structures. When making a structure, it’s important to use simple ways to make it strong. Buildings, bridges, ...

It's driving me nuts. Is the double bond constantly changing between all possibilities fast enough that it shortens the bond length for all, or are all the double bonds existing in all possible states ...