Why does sodium and potassium ions need a protein pump to pass through the cell membrane? A. The ions have a charge and cannot pass directly through the cell membrane.
B. The ions are moving against the concentration gradient.
C. Energy is needed to move the ions.
D. All of the above.

Drag each tile to the correct box. match the given symbol or molecular formula to the term that best describes it. element -organic compound -inorganic elemental molecule -inorganic compound -answers given: so2, k, ci2, c6h6

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).

Which to produce involved from a symbiotic relationship of organisms which resulted in eukaryotic organisms contain chloroplast