All living things have certain characteristics. The genetic code carries the directions for inheritance, and offspring usually resemble their parents. With , offspring have the same traits as their parents. With , offspring differ from their parents in some ways. Living organisms use energy and materials to grow, develop, and reproduce. These life processes involve a set of chemical reactions called . Organisms have means of detecting a change in their environment and responding to this . Most organisms require that their internal environments remain in a fairly constant range, and so they maintain . The ability of a group of organisms to change, or , over time is necessary for survival in an ever-changing environment.

Proteins are the workhorses of the cell, controlling virtually every reaction within as well as providing structure and serving as signals to other cells. proteins are long chains of  amino acids  , and the exact sequence of the amino acids determines the final structure and function of the protein. instructions for that sequence are encoded in  genes  . to make a particular protein, a messenger ribonucleic acid (mrna) copy is made from the gene (in the process called  transcription  ), and the mrna is transported to the  ribosome  . protein synthesis, also called  translation  , begins when the two ribosomal subunits link onto the mrna. this step, called initiation, is followed by elongation, in which successive amino acids are added to the growing chain, brought in by transfer rnas (trnas). in this step, the ribosome reads the  nucleotides  of mrna three by three, in units called  codons  , and matches each to three nucleotides on the trna, called the anticodon. finally, during termination, the ribosome unbinds from the mrna, and the  amino acid  chain goes on to be processed and folded to make the final, functional protein

C) they are specialized meaning they are designed to do different things