The principal microtubule-organizing center in animal cells is the a. centrosome. b. centromere. c. kinetochore. d. cell cortex.

What enzyme is most important for dna replication and why?

Ras is a g-protein that is activated when a growth factor attaches to egfr. its activation results in the replacement of a gdp molecule with a gtp molecule, thus allowing a signal transduction pathway to be activated. considering the signal pathway illustrated on this page, what is one potential outcome of a mutation in the ras gene that leads to ras protein hyperactivity. be specific.

Which of the following forest management practices is best for reestablishing areas of forest?