Sort the following phrases as descriptions of alpha helices, beta turns or all alpha Helices 1st residue hydrogen- bonded to 5^th residue (that is, residue n is H- bonded to residue n + 4) all - NH groups point in the same direction Beta Sheets successive R groups point in opposite directions Beta Turns 1^st residue (that is, residue n is H- bonded to residue n+3 All contains-NH hydrogen bonded to C = O