Define emergent property in reference to the levels of organization of living organisms

An emergent property is a property which a collection or complex system has, but which the individual members do not have. A failure to realize that a property is emergent, or supervenient, leads to the fallacy of division.

In chemistry, for example, the taste of saltiness is a property of salt, but that does not mean that it is also a property of sodium and chlorine, the two elements which make up salt. Thus, saltiness is an emergent or a supervenient property of salt. Claiming that chlorine must be salty because salt is salty would be an example of the fallacy of division. 

In biology, for example, heart is made of heart cells, heart cells on their own don't have the property of pumping blood. You will need the whole heart to be able to pump blood. Thus, the pumping property of the heart is an emergent or a supervenient property of the heart. Claiming that an individual heart cell can pump blood because the heart can would be an example of fallacy of division.