Amino acids have the generic structure seen below, where r represents different carbon-based side chains.
describe how the structure of amino acids allows them to be linked into long peptide chains to form proteins.

When the intestine becomes infected with the food borne illness bacteria e. coli, the bacteria releases a enterotoxin that causes excessive loss of water and electrolytes in the intestines. necessary to return the osmolality of the intestines to normal?

In dna, only the_ varies from one nucleotide to another. base phosphate sugar amino acid

The kidney filters potentially toxic substances in the blood, and thus “clears” the blood of those substances. this clearance function is dependent upon and proportional to the diffusion gradient of the substance across filtering capillaries, i. e. if the concentration of the substance is doubled, twice as much will be cleared from each ml of blood that is filtered. suppose that the body produces a constant amount of a substance x per unit of time. the kidneys eliminate substance x at a rate directly proportional to the concentration of the substance and the volume of blood cleared each minute (c): elimination = c × [x], where [x] is the steady-state concentration of substance x. imagine an individual with an initial concentration of x equal to [x]0 who develops kidney disease. her baseline clearance c0 drops to one half of the original (½c0). what is the new steady state concentration of x? (for simplicity, assume that substance x is 100% filtered by the kidney).