The rapid depolarization phase of the action potentials of myocardial contractile cells is due to which ion(s)? The rapid depolarization phase of the action potentials of myocardial contractile cells is due to which ion(s)? Na+ only Ca2+ only K+ only both Ca2+ and K+ both Na+ and K+

In many humans, exposing the skin to sunlight over prolonged periods of time results in the production of more pigment by the skin cells (tanning). this change in skin color provides evidence that -

One function of the poly-a tail on eukaryotic mrna sequences is to the mrna be transported from the nucleus to the cytoplasm. prokaryotic mrna also has a poly-a tail. choose the best explanation of the prokaryotic poly-a tail. a. prokaryotic poly-a tails are composed of a different molecular structure compared with eukaryotic poly-a tails. b. prokaryotic poly-a tails have the same functions as eukaryotic poly-a tails, because this process is highly conserved throughout different species. c. prokaryotic poly-a tails aren't important, because prokaryotes don't have nuclei. d. prokaryotic poly-a tails have other functions,because prokaryotes don't have nuclei.

Stem cells found adult tissue such as in bone marrow brain muscle skin and liver are only capable of what