Comprehensive biology
what process is thought to have changed the genetic code over billions of years?

Which prevent errors in dna replication? a. helicase enzyme checks the dna for errors. b. each base can attach to only one other type of base. c. ribosome enzymes prevent errors from happening. d. dna contains no complementary base pairs.

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.)

How do cells grow and reproduce to maintain homeostasis?