The Structure of the ANS System and the Effects it Has Shown to Have on Physiological and Behavioral Functions
The ANS is a purely motor system, meaning that it transmits impulses out of the CNS to various motor or effect or organs of the body. These include the smooth muscle of the blood vessels and the gastro intestinal system, heart muscle, and several glands such as the pancreas, the adrenal medulla and the salivary glands. The ANS first function is to regulate internal bodily processes. It does this by sending information to and from the CNS. Although the ANS is very important it is the CNS that is in control.
The ANS operates as an independent or autonomous control system. Although we learn as we mature in age to control our autonomic functions, such as urination and defecation, these would occur in the absence of control of them. These bodily processes and many others are controlled by the ANS without requiring conscious effort. To enable the ANS to perform its functions it has two branches. The sympathetic branch that produces a pattern of arousal in the body, with heart rate and blood pressure increased, adrenaline released and from the adrenal gland. The parasympathetic branch run to the same organs, but their activation leads to opposite effects. Heart rate and blood pressure are reduced, adrenaline secretion falls, and digestive activity increases.
The sympathetic branch or ganglia of neurons comprising the sympathetic branch are interconnected so that they form a long chain on each side of the spinal cord. The sympathetic branch originates in the two middle portions of the spinal cord; the interconnections between the neurons allow the sympathetic branch to act as a unit. It is important because the sympathetic branch prepares the body to extend energy. As well as the effects show in the diagram below
It also increases blood pressure, releases sugar from the liver into the blood and increases the blood flow to the muscles used in physical action. Further, it tells the endocrine system to release hormones into the bloodstream to strengthen these...