Organic CompoundsLipids-constituent of fat: a biological compound that is not soluble in water, e.g. a fat.Carbohydrates-energy component of diet: a biological compound containing carbon, hydrogen, and oxygen that is an important source of food and energy.Protein-complex natural compound: a complex natural substance that has a globular or fibrous structure composed of linked amino acids.Nucleic Acids-acid found in all living cells: an acid of high molecular weight, e.g. DNA or RNA, consisting of nucleotide chains that convey genetic information and are found in all living cells.Characteristics of Living ThingsCells-basic unit of living thing: the smallest independently functioning unit in the structure of an organism, usually consisting of one or more nuclei surrounded by cytoplasm and enclosed by a membrane.Energy-ability to do things: the ability or power to work or make an effort.Evolution-theory of development from earlier forms: the theoretical process by which all species develop from earlier forms of life.Heredity-passing on of genetic factors: the transfer of genetically controlled characteristics such as hair color or flower color from one generation to the next in living organisms.Homeostasis-state of equilibrium: a state of equilibrium or a tendency to reach equilibrium, either metabolically within a cell or organism or socially and psychologically within an individual or group.Interdependence-a relationship in which each member is mutually dependent on the others. This concept differs from a dependence relationship, where some members are dependent and some are not.