Final answer:
In biology, ΔH is the change in enthalpy, representing the heat content of a system at constant pressure, and it is the sum of the change in internal energy and the product of pressure and volume changes.
Step-by-step explanation:
In biology, ΔH refers to the change in enthalpy, a term used to describe the thermodynamics of chemical and physical processes. The equation ΔH = ΔE + Δ(PV) indicates that change in enthalpy (ΔH) is the sum of the change in internal energy (ΔE) and the change in the product of pressure and volume (Δ(PV)). Since ΔH indicates the heat content of a system at constant pressure, it represents the heat absorbed or released by a reaction under these conditions. Enthalpy is a state function, implying that only changes in enthalpy for certain processes can be determined, not their absolute enthalpy values.