Pg. 68-69 reading 4/6/13
• The many kinda of plastics you use every day are polymers. Polymers are also essential to the
structure and function of organisms.
• Plants use starch to store extra sugar. Cellulose is the primary structural constituent in plant
tissues; it is also one of Earths most abundant organic molecules.
• The 20 amino acids found in all organisms have different chemical structures, but each has a
nitrogen-containing amino group and a carboxylic acid group.
• Each nucleotide is composed of a five carbon sugar, a phosphate group, and a nitrogenous base.
• Each nucleotide of DNAcontains the sugar deoxyribose and one of four nitrogenous bases-
adenine, thymine, cytosine, or guanine. (adenine always pairs with thymine, and cytosine
always pairs with guanine)
• The nucleotides of RNAcontain the sugar ribose rather than deoxyribose and nitrogenous base
uracil rather than thymine.
• The sequence of triplets of nucleic acids in the RNAstrand determines the sequence of amino
acids in the newly synthesized protein.
• Macromolecules:Alarge complex molecule composed of small organic molecules linked to one
• Polymers: Simple molecules linked together to form much larger chains or networks.
• Polysaccharides: Polymers of simple s