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 can fuse with the plasma membrane, releasing their contents outside the cell. Vesicles are a basic tool of the cell for organizing metabolism, transport, enzyme storage, as well as being chemical reaction chambers. Many vesicles are made in the Golgi apparatus, but also in the endoplasmic reticulum, or are made from parts of the plasma membrane. Source(s): for the diagram and more info on vesicle formation refer: http://en.wikipedia.org/wiki/Vesicle_%28...