Chemical Messengers 3. Hormones â¢Longârange messengersâ¢Secreted into blood by endocrine glands in response to appropriate signalâ¢Exert effect on target cells some distance away from release site 4.hemical Messengers 3. Hormones â¢Longârange messengersâ¢Secreted into blood by endocrine glands in response to appropriate signalâ¢Exert effect on target cells some distance away from release site 4.
Scale box in millimeters. Vesicular texture is a volcanic rock texture characterized by a rock being pitted with many cavities (known as vesicles) at its surface and inside.
Vesicles are air bubbles that form in extrusive igneous rock. What sub-type of igneous rock contains vesicles and why does it contain them? Vesicles are commonly found in extrusive igneous rock because of gases that form from lava as the material solidifies -- like bubbles in a bottle of soda when you open it.