Q1. In a protein complex for the light reaction (a reaction center), energy is transferred from pigment molecule to pigment molecule, to a special chlorophyll a molecule, and eventually to a primary electron acceptor. Why does this happen?

Q2. Muscle cells, while an individual is exercising heavily and when muscle becomes oxygen deprived, convert pyruvate to lactate. What happens to the lactate in skeletal muscle cells?

Q3. Two substances in the glass beaker chemically react, and the glass beaker becomes too hot to touch, if the two substances are defined as the system, what constitutes the surroundings?