Structure and Function of Arteries, Capillaries, and Veins. The walls of arteries and veins have three layers or tunics: 1  An outer layer (tunica adventitia) of connective tissue with collagen fibers. 2  A middle layer (tunica media) of circularly arranged smooth muscle and elastic fibers.
You might have heard that eating chocolate or greasy foods can cause acne, but these are both just myths. The truth is that food has little to do with breakouts. Acne occurs when the openings of hair follicles become blocked with oil secretions, dead skin cells and bacteria.
Experts aren't sure why drinking soda is linked to osteoporosis. It may be simply that the soda is displacing healthier drinks in your diet.If you're guzzling a Pepsi with dinner (or breakfast !) you're probably not drinking the glass of milk or fortified orange juice that nutritionists recommend.t may be simply that the soda is displacing healthier drinks in your diet. If you're guzzling a Pepsi with dinner (or breakfast !) you're probably not drinking the glass of milk or fortified orange juice that nutritionists recommend.