the science calorie (little c) is a measure of heat energy the food calorie (big C) is a measure of energy that we burn, but it is equal to 1,000 science calories so 1 big C is equal to 1,000 little c's.
Protists are a group made up of protozoa, unicellular algae, and slime molds. We will concentrate on the animal portion of this group: the protozoa (proto = first, zoa = animals).
Unicellular protozoa and algae are unicellular eukaryotes. Pluricellular algae are also eukaryotes of simple structure. Protists are believed to be the phylogenetic ancestors of the living organisms of the other eukaryotic kingdoms (fungi, animals and plants).