The structure of an organic molecule as it appears on paper can be very different when drawn by different people. Look up the structure of the amino acid threonine on the page of amino acid structures. Which of the following structure(s) is(are) the structure of threonine? In other words, which of the following molecules are conformers of threonine? HC-CH-OH 1. 3. I HN-CH-C-OH HC-CH3 OH H3C-CH-CH-C=O OH NH OH 2. HN- HO - CH