Endocrine gland hormones at target cells "Permissiveness" is the situation in which a hormone cannot exert its full effects without the presence of another hormone. "Synergism" occurs when two or more hormones produce the same effects in a target cell and their results are amplified. "Antagonism" occurs when a hormone opposes or reverses the effect of another hormone. The endocrine glands belong to the body's control system. The hormones which they produce help to regulate the functions of cells and tissues throughout the body. Endocrine organs are activated to release their hormones by humoral, neural or hormonal stimuli. Negative feedback is important
Gastric glands the fundus and body of the stomach. They are simple almost straight tubes, two or more of which open into a single duct. "Oxyntic" means acid-secreting and they secrete hydrochloric acid (HCl) and intrinsic factor. The pyloric glands are located in the antrum of the pylorus. They secrete gastrin produced by their G cells. There are millions of gastric pits in the gastric mucosa and their necessary narrowness determines the tubular form of the gastric gland. More than one tube allows for the accommodation of more than one cell type. The form of each gastric gland is similar; they are