AP BIOLOGY

Detailed explanation-1: -Therefore, proteins are long chains of amino acids held together by peptide bonds. The actual order of the amino acids in the protein is called its primary structure and is determined by DNA. The order of deoxyribonucleotide bases in a gene determines the amino acid sequence of a particular protein.

Detailed explanation-2: -A protein molecule is made from a long chain of these amino acids, each linked to its neighbor through a covalent peptide bond (Figure 3-1). Proteins are therefore also known as polypeptides.

Detailed explanation-3: -Nucleic acids are polynucleotides-that is, long chainlike molecules composed of a series of nearly identical building blocks called nucleotides. Each nucleotide consists of a nitrogen-containing aromatic base attached to a pentose (five-carbon) sugar, which is in turn attached to a phosphate group.

Detailed explanation-4: -DNA and RNA are composed of nucleotides that are linked to one another in a chain by chemical bonds, called ester bonds, between the sugar base of one nucleotide and the phosphate group of the adjacent nucleotide.

Detailed explanation-5: -DNA and RNA are polymers (in the case of DNA, often very long polymers), and are made up of monomers known as nucleotides. When these monomers combine, the resulting chain is called a polynucleotide (poly-= “many").