When would a cell be expected to use an active transport mechanism to move a substance from the outside environment into the cytoplasm? A: when a concentration gradient exists and more of the substance is on the inside of the cell

B: when a concentration gradient exists, and the same amount of substance is found inside and outside the cell

C: when no concentration gradient for the substance exists across the cell membrane

D: when a concentration gradient exists and more of the substance is on the outside of the cell

Amylase is an enzyme found in the human digestive system. why do you think it was important to keep the enzyme temperature above 37 degrees celsius (98.6 degrees f)? describe what might happen if the temperature decreased by 10 degrees celsius.

Heat from earths interior and pressure from overlying rock transform the remains of marine sediments into

The dna in a cell’s nucleus encodes proteins that are eventually targeted to every membrane and compartment in the cell, as well as proteins that are targeted for secretion from the cell. for example, consider these two proteins: phosphofructokinase (pfk) is an enzyme that functions in the cytoplasm during glycolysis. insulin, a protein that regulates blood sugar levels, is secreted from specialized pancreatic cells. assume that you can track the cellular locations of these two proteins from the time that translation is complete until the proteins reach their final destinations.for each protein, identify its targeting pathway: the sequence of cellular locations in which the protein is found from when translation is complete until it reaches its final (functional) destination. (note that if an organelle is listed in a pathway, the location implied is inside the organelle, not in the membrane that surrounds the organelle.)