Having peptides arranged in a beta sheet would be an example of a secondary structure A) True B) False

Shown below is an internal fragment of a polypeptide. If this polypeptide were growing, onto which end would the next amino acid be added? a) Onto the right  b) Onto the left

1) If the pH of the rain drops from 6 to 5 due to air pollution, the rain has become: a) two time more acidic b) four-time more acidic c) ten time more acidic d) one thousand times more acidic 2) which of combination of statement is correct ? the denaturation of protein  1- causes changes in tertiary structure 2- is always an irreversible process 3-has no influence on the solubility 4-occurs only by interaction with heavy metals 5-does not influence covalent bonds and hydrogen bonds select one: a) only 1 is correct b) only 1 and 2 are correct  c) only 3 and 4 are correct d) only 3, 4 and 5 are correct  e) only 1, 2 and 5 are correct

1. Which best describes the contribution of primary (1’) structure of polypeptides to the native conformation of proteins: a) Structure that results from intrachain interactions of amino acid side chains b) Structure that results from interchain interactions of amino acid side chains c) Structure that results from base pairing d) Structure that results from the linear sequence of amino acids from beginning to end of molecule.