The three changes of state during which energy is absorbed are:
1. Change from solid to liquid - Melting.
2. Change from liquid to gas - Vaporization
3. Change from solid to gas - Sublimation
All these changes of state require heat energy to break the attractive forces that hold the particles of the molecules together, so that they can move into more disorderly states. For instance, when heat is applied to a solid, the solid absorbs the heat and use it to break the attractive forces that are holding the molecules of the solid together. At a particular temperature, the attractive forces will be completely overcome and the solid framework will collapse, thus leading to the melting of the solid.
An autotroph is an organism that can produce its own food.
Excess carbs and fats are stored; excess proteins are not.
Excess calories are transformed as fat when in excess, which includes protein.
I believe the term for an observable trait of an organism would be called or noted as the organism's phenotype.
