Quantum uncertainty in cell functions In class today (philosophy of the mind) we discussed the ideas of Richard Lewontin. He stated that in determining the phenotype of a gene we must take into account the environment but also quantum uncertainties. Many people did not understand what these uncertainties might be. I would like to email the class and explain it to them, here is my draft. Does it make sense? What might I change to be more correct if I am not?

I wanted to add this at the end of class, but I couldn't think of
  something short and sweet. Also I'm not a quantum physicist, but I
  have read a lot on the subject.
The uncertainty rests upon the quantum superposition principle. The
  superposition principle tells us that any quantum particle (quarks,
  leptons(electrons are in this category), and bosons) can and do exist
  in a super position of many possible physical states at a single time.
  Only when it comes to measurement can we tell the actual state out of
  the superposition of states that the particle is going to take. Each
  state that a particle can take has a probability of happening.
This is hard to understand in our macroscopic world because everything
  has one definite physical state. But at the microscopic level
  subatomic particles can have multiple physical states simultaneously,
  but only when it comes to interactions with other microscopic objects
  do they take a single form. And the forms that a subatomic particle
  can take each have a probability of happening. (The idea of a particle
  taking a single physical form is called "collapsing the wave
  function")
So within a cell there might be an atom with constituent sub-atomic
  particles. Pick one, it might be in a superposition of states A and B.
  Only when this particle comes to interact with another does it take to
  either state A or B. Furthermore each state A and B have a probability
  of of happening. So there is an uncertainty involved in the cell interactions.

EDIT.
I guess that is kind of botched. Lets ask the real question. What quantum uncertainties are present in physiology that would need to be taken into account when determining phenotype?
 A: I strongly suspect that his argument is utter garbage. Is his intent to argue that since phenotypes arise due to cellular interactions that depend on chemical reactions which proceed by quantum-mechanical dynamics, then phenotypes depend on quantum dynamics? If so, then his statement is true, but vacuously so. 
As John and Ignacio pointed out, quantum dynamics play a role in the interactions of atoms and small molecules, but for anything larger than that, the reactivity of objects like chemical functional groups is well-known and highly deterministic (ask any synthetic organic chemist). At the level of larger molecules like proteins and carbohydrates, behavior is almost entirely classical in nature; qualities like the folding of small proteins and the behavior of rhodopsin in the eye are modeled in an almost entirely classical manner when computationally feasible. And at the level of macroscopic phenotypes like hair color and BMI, you're not even close to being in the realm of relevance anymore.
To argue that the development of phenotypes is strongly dependent on quantum-mechanical axioms of dynamics is sort of like arguing that the presence of cosmic rays will influence the taste of a bowl of cereal because the rays might pass through your brain and change the neural signals slightly. It's technically true by the most extreme leap of logic imaginable, but if you say it, people will still think you're an idiot.
A: In most chemical reactions there is a barrier, that is an activation energy, to the reaction. This barrier controls the reaction rate: a high barrier means a low rate and a low barrier means a high(er) rate. In most cases the reagents get through the barrier because there is a distribution of thermal energies and a small fraction of the reagents have enough energy to get over the barrier. This is an entirely classical effect. However quantum tunneling through the barrier must play some role, if only a small one.
Speaking as one almost entirely ignorant of the mechanics of gene expression I would guess that the rate of expression is controlled by similar dynamics, and therefore it's just conceivable that quantum tunneling would play some part. However, given the size of DNA molecules I'd bet it's a very small part. In any case you're talking about minor changes in the rate of expression, and certainly nothing like determining whether expression was suppressed.
