•determine concentration of enzyme stock solution, if unknown, by taking an a280 nm reading of a 1: 100 dilution (in water). use a total volume of 1 ml in the cuvette.
• dilute some of the enzyme stock with buffer a to make a 4 mg/ml solution.
• serially dilute the 4 mg/ml solution with buffer a to make working solutions of 400 µg/ml and 40 µg/ml.
• prepare 30 µl of each working solution for every sample
the pi of the lab gives you a tube of enzyme and tells you the following before disappearing into the office to write more grant proposals:

➢ there is 50 µl of enzyme stock solution. the enzyme is expensive to purify, so follow the protocol exactly, using as little of the stock solution as possible.
➢ the concentration of the stock solution is currently not known, but a 1 mg/ml concentration of the pureenzyme has an a280 nm of 2.0.
➢ you’ll be performing the assay on 12 samples.
➢ make enough of each working solution so that you have at least 400 ul to work with when you do the assay (to cover any waste and/or inefficiencies in pippetting).
using the spectrophotometer to read the absorbance at 280 nm, you get a reading of 0.784.

1. (2 pts) what is the concentration of the solution in the cuvette? what is the concentration of the stock

gametes or germ cells are haploid cells (example: sperm and ova) containing only one set (or n) number of chromosomes and autosomal or somatic cells are diploid cells containing 2n number of chromosomes.

this protocol provides a detailed procedure for agarose-based ip to purify and enrich the protein of interest.

a. by using fur or clothes to trap heat energy near the body

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.