Quantum biology is the study of quantum mechanics, theoretical chemistry, and biology. This study cannot be explained by classical physics. This is why quantum mechanics must be used.
In biology, there are many processes that involve quantum mechanics. For example, converting (or changing) energy into different forms uses quantum mechanics. Chemical reactions, light absorption, forming excited electronic states and transfer of excitation energy all involve quantum mechanics and biology. Also, electrons and protons (hydrogen ions) move in chemical reactions. These processes make photosynthesis, olfaction and cellular respiration happen.
Quantum biology can use math computations (or calculations) that explain the effects of light in biology.
Quantum biology studies important and unexpected things that happen while studying quantum biology. These important and unexpected things are called "non-trivial quantum phenomena". These phenomena use physics to explain complicated biology processes. However, the physics in quantum biology is very hard to study.
There are 4 common biology processes that are affected by quantum mechanics. These are enzyme catalysis, sensory processing, energy transfers, and information encoding.
Enzymes are biological catalysts. This means they are living molecules (usually a protein) that makes the reaction rate (or speed) of a chemical reaction go faster. Scientists have learned that enzymes might use quantum tunneling in electron transport chains. Electron transport chains move an electron from one place to another. Enzymes could possibly use quantum tunneling to move electrons along the transport chain. Quantum tunneling lets more energy to move moved through the electron transport chain.
Proteins have four structures. These structures organize how the protein is formed. The fourth structure is called the protein quaternary structure. Scientists think that the quaternary structures in enzymes have adapted to let quantum entanglement and coherence happen in themselves. Quantum entanglement and coherence are needed for quantum tunneling to happen.
In quantum tunneling, electrons and protons are transferred, or moved. The protons are in the form of an hydrogen ion, or H+. Quantum tunneling is when a subatomic particle moves through a "potential energy barrier". In classical physics, the particle would be reflected off this barrier because it does not have enough energy. In quantum tunneling, the particle moves past this barrier. Particles are able to do this because of complementarity. Complementarity is when measuring something changes the thing. Since electrons and protons are both waves and particles, they can move through potential energy barriers.
In physics, a semiclassical (SC) physics is useful in explaining this process. This is because it involves both quantum objects (e.g. particles) and larger objects (e.g. biochemicals).