3. The following figure shows drug molecules (AMT, IMP, PMT) that bind with DNA. DNA is a polymer with anionic phosphate groups (PO33) sticking outside and a hydrophobic core. Indicate which part of the drugs shown below will have thermodynamically favourable interactions with the phosphate group on the DNA molecule and why. What will happen to the rest of these molecules (AMT, IMP, PMT) during this interaction? Explain using words and drawings. DNA binding drugs 4. The following figure shows the structure of a peptide (made of amino acids). Peptides and proteins are like ribbons and can fold on itself forming a 3D structure. Pay attention to the functional groups in the boxed areas. When this solid peptide is added to water, identify A) the functional groups that will dissolve in water, and B) the functional groups that will not dissolve in water. Explain the contribution of S and H towards the spontaneous folding of this peptide. Spontaneity of processes is indicated by a negative G(=H+TS) or a positive S yolverse. Scenario 1: There are processes where the H is large and negative (exothermic) and although the contribution of S is insignificant, the G is still negative. Scenario 2: Similarly, there are processes where H is very small, but S of the universe is so large that the process becomes spontaneous. Fill in the blank spaces with appropriate sign (+ or - ) and a qualitative value (large or small) using the information presented above. Using this idea and your answer above, identify which of the scenarios (1 or 2) is taking place when two or more non-polar groups from the peptide interact with each other, instead of interacting with the solvent