The book is Essentials of Anatomy & Physiology
. I don't have it with me at the moment and don't know the author offhand.
You are correct. For the second part, you are also correct, but the answer I was looking for was that the epidermal ridges help get nutrients into the epidermis because the epidermis doesn't have it's own blood vessels.
There are tons of authors who have written a book with that title...>_>
Um...I think that's kinda debatable...I suppose that works, but even then, dermal papillae exist throughout your skin, right? Epidermal ridges don't, they exist in certain parts of the skin. I imagine the density of the blood vessels in the papillary region is the primary source of its nutrients...but then again, I suppose thick skin could use the extra help in getting the nutrients that way, since it's thicker than thin skin.
Whatever, that was the most obvious answer to me
Anyway, next question (I'm bringing this back to the nervous system
): describe the anatomical differences between the sympathetic and parasympathetic divisions of the autonomic nervous system in terms of motor output, the location of ganglia, and differences in the preganglionic & postganglionic fibers of both divisions