if shell fragments are found in a rock sample, it is most likely
that the rock formed

a) on a mountian slope
c) from magma
b) on a glacier
d) in shallow water

Along with the kidneys, the ureters, bladder, and urethra make up the urinary system. match each function or description to the appropriate structure.

The activity of the modern sample is 1.10 bq . how long does that measurement take?

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).