Bob, a student taking 7.012, looks at a long-standing puddle outside his dorm window Curious as to what was growing in the cloudy water, he takes a sample to his TA, Brad Student. He wanted to know whether the organisms in the sample were prokaryotic or eukaryotic

Many intracellular proteins are required to interact or bind to other macromolecules within a bind DNA. Such proteins often have conserved structural features, called motifs, whis at can cell in order to function properly. One class of such proteins is comprised of proteins tha interact with DNA. One such motif consists of two closely aligned a-helices(shown as cylinders below)that each have leucine-rich regions. This motif is referred to as a leucine

Please print out this problem set and record your answers on the printed copy. Answers to this problem set are to be turned in at the box outside by 4: 10 Wednesday, September 17. Problem sets will not be accepted late. Solutions will be posted on the web

Please print out this problem set and record your answers on the printed copy. Answers to this problem set are to be turned in at the box by 4: 10 Wednesday, September10. Problem sets will not be accepted late. Solutions will be posted on the web

A recent study of controlled release of a model small-molecule drug from poly(lactide-co-glycolide) microspheres prepared by the single-emulsion method found that the diffusion constant of the drug through the polymer was best related to the polymers molecular weight according

1. Re-derive the equation for equilibrium swelling of a polyelectrolyte gel where the polymer chains contain a basic ionizable group that becomes positively charged with decreasing pH

1. Two hydrogels are prepared from two different candidate polymers for controlled release of a protein drug, interleukin-2(IL-2). The gels exhibit the same swelling ratio at equilibrium, but gel A(formed by cross-linked polymer A, repeat unit molecular weight Mo= 100 g/mole)has

1. Re-derive the equation for equilibrium swelling of a polyelectrolyte gel where the polymer chains contain a basic ionizable group that becomes positively charged with decreasing pH

5 points/problem(20 points total) 1. Two hydrogels are prepared from two different candidate polymers for controlled release of a protein drug, interleukin-2(IL-2). The gels exhibit the same swelling ratio at equilibrium, but jel a (formed by cross-linked polymer A, repeat unit molecular weight Mo= 100 g/mole)has a molecular weight between cross-links of 3,000 g/mole, while gel B (formed from cross linked polymer B, Mo=95 g/mole) has a molecular weight between crosslinks of

A recent study of controlled release of a model small-molecule drug from poly (lactide-co-glycolide) microspheres prepared by the single-emulsion method found that the diffusion constant of the drug through the polymer was best related to the polymer's molecular weight according to