A molecule that moves across a cell membrane without using the cell’s energy tends to move A. away from the area of equilibrium.
B. away from the area where it is less concentrated. C. away from the area where it is more concentrated. D. toward the area where it is more concentrated.
C. away from the area where it is more concentrated.
Explanation:
If a molecule is moving across a cell membrane w/o using the cell's energy, it is diffusion, which is defined as the movement of a substance from higher to lower concentration. Diffusion <em>never </em>requires energy, whether it is facilitated or not, as clustered molecules and/or atoms simply want to get the heck away from each other if in too high concentration in a single place. The type of molecular movement across a cell membrane that would require the cell's energy would be active transport, which often requires ATP or GTP and works against a concentration gradient.
half of the original c-14 isotope remain in the fossil 5730 years after the organisms died. 1/4 of the original isotope will remain 5730 years after that or 11460 years after the organism died.
The tissue level or organization refers to a group of cells of the same origin that carry out a specific function. It can be viewed as a group of cells that don't necessarily make up an organ. The tissue level or organization refers to a group of cells of the same origin that carry out a specific function.
