Which of the following is true of dna? a. there are six nitrogenous bases involved. b. cytosine can pair with guanine and adenine. c. there are four nitrogenous bases involved. d. adenine always pairs with guanine.

You have just sequenced a new protein found in mice and observe that sulfur-containing cysteine residues occur at regular intervals. what is the significance of this finding? it will be important to include cysteine in the diet of the mice. cysteine residues are required for the formation of α helices and β pleated sheets. cysteine residues are involved in disulfide bridges that form tertiary structure. cysteine causes bends, or angles, to occur in the tertiary structure of proteins.