What is the net charge of histidine at pH = pKa2?(pKa1 = 1.8, pKa2 = 6.0, pKa3 = 9.3

You have a solution that contains phospholipid vesicles in a test tube. these vesicles have phospholipid bilayers, but do not contain any membrane transporters. you add a number of different molecules to the solution, and wait a period of time for them to equilibrate. if you could measure the concentration of each molecule, for which of the following would you expect to measure equal concentrations inside and outside of the vesicles? assume for this question that the overall osmolarity inside and outside the vesicles is the same (that is, there is no appreciable diffusion of water across the membrane). (select two answers) an amino acid with a hydrophobic side-chain a small non-polar molecule a negatively charged ion a small polar molecule a small lipid hormone

Below, the levels of organization in a multicellular organism are shown from least to most complex. which level of organization can be described as several different types of tissues working together to perform a common task?

Which statement explains how gravity and intertia work together