A sample of milk is tested for its bacterial content in a plate count assay. This sample is diluted in a 1:10 dilution series the tube of a dilution factor (101) is plated in a pour plate. After incubation, the plate has 47 colonies. Calculate the concentration of bacterial cells in the original milk sample. U A

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

In which case would a scientist choose to use a dissecting microscope rather than a compound microscope

List the advantages and disadavantages of the switch from persistent chlorinated hydrocarbon pesticides (such as ddt) to nonpersistent organophosphate pesicides. have the benefits of the switch outweighed the disadvantages? explain.