On the face of it the weirdness of quantum mechanics and biology would seem to have nothing to do with each other. Quantum mechanics deals with the subatomic world and biology with much larger things like cells. Any quantum effects in cells would be cancelled out by the multitude of noisy biological processes. But not so. Quantum biology refers to the many biological processes that involve the conversion of energy to usable chemical transformations and are quantum mechanical in nature.

Examples are photosynthesis, vision, magnetoreception in animals, DNA mutation, and the conversion of chemical energy into motion. Any process that involves the transfer of electrons and protons in chemical processes uses quantum mechanical effects. In photosynthesis it has been shown that the wave and particle conundrum occur simultaneously. The wave spreads uniformly to potential receptors, while the particle follows the path of least resistance through the field of potential created by the wave. This makes for a 95% efficiency in energy transfer.

Many important biological processes taking place in cells are driven and controlled by events that involve electronic degrees of freedom and, therefore, require a quantum mechanical description. An important example are enzymatically catalyzed, cellular biochemical reactions. Here, bond breaking and bond formation events are intimately tied to changes in the electronic degrees of freedom. For more quantum biology examples, click here.

Finally in neuroscience there is a debate as to whether the brain is a quantum computer -- that the microtubules within neurons have the capability to perform quantum computation . Stuart Hameroff  believes that the tubulin subunits which make up a microtubule are able to cooperatively interact in a quantum computational sense.