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.
Both andesite and vesicular andesite formed at or near the surface (extrusive). This results in fast cooling and a fine texture (crystals are less than 1mm). The difference is that vesicular andesite formed from magma containing dissolved gas which escaped while the magma was cooling.ndesite, Vesicular Andesite & Diorite. All three of these rocks form from the same minerals: Mostly plagioclase feldspar with some quartz, biotite and amphibole (see blue zone in the diagram below).