AP BIOLOGY

Detailed explanation-1: -What structure mediates and controls the formation of polypeptides?-Ribosome. What’s polypeptide?-Polypeptides are polymers of amino acids-joined together by peptide bonds.

Detailed explanation-2: -Ribosomes are the sites in a cell in which protein synthesis takes place.

Detailed explanation-3: -Amino acids have a central carbon attached to an amino group, a carboxyl group, a hydrogen atom, and a variable R group. The R group gives the amino acid its function and the specific combination of amino acids in a polypeptide chain will ultimately give the protein its structure and function.

Detailed explanation-4: -The ribosomes bind to tRNA and amino acid to facilitate the formation of the polypeptide chain, and following it; they are dissociated from each other. The structure of ribosomes is specially equipped to hold tRNA, amino acids, and the mRNA molecule.

Detailed explanation-5: -Polypeptides are formed when the amino group of one amino acid forms an amide (i.e., peptide) bond with the carboxyl group of another amino acid (Figure 15.5. 1). This reaction is catalyzed by ribosomes and generates one water molecule.