The endocrine system is a system that gives off hormones to facilitate growth, reproduction and metabolism in the bloodstream. A major example is the pineal gland which includes; melatonin, the pituitary gland, the thyroid, the parathyroid, the thymus and the adrenal gland. Melatonin is most important in sleeping and also controls sexual development. The pituitary gland is responsible for stimulating growth. The thyroid gland is located in the throat with the principle of producing hormones, which is significant to metabolism and growth. The parathyroid controls phosphorus levels which lowers blood concentration, and blood calcium which released calcium from bone into the bloodstream. The thymus is located in between the breastbone and the heart. The thymus is vital to a newborn but has little importance in adults. The adrenal gland consists of the adrenal cortex and the adrenal medulla which generates epinephrine and norepinephrine. Epinephrine and norepinephrine are both similar chemically and they both have about the same actions on the body, they together amplify heart contractions, blood productivity and blood pressure. Organs that contain endocrine tissue include; the pancreas, the gonads (ovaries and testes), and the hypothalamus. There are also hormone producing structures that include; adipose tissue which is connective tissue that mostly consists of fat cells, the wall of the small intestine, the stomach, the kidneys, and the heart. Hormones are chemicals secreted into cellular fluid and then they are absorbed into the bloodstream. There are two major types of hormones the amino and the steroid.
The brain is divided into three main structures; the hindbrain, the midbrain, and the forebrain. The Hindbrain consist of three divisions; the pons, the cerebellum, and the medulla. The pons helps the body make movements from one side of the body to the next; it also connects the medulla and the cerebellum. The cerebellum is most important in supporting equilibrium and managing movements. The medulla manages breathing and heartbeat. The midbrain is one of the smallest areas of the brain which also plays a great role in visual and auditory information. The forebrain is one of the largest areas of the brain; it consists of the corpus callosum and the cerebral cortex. The corpus callosum connects the two hemispheres of the brain, the right and the left. The cerebral cortex is the outer most covering of the forebrain. It is divided into four lobes; the limbic system, the frontal lobe, the parietal and the temporal lobe. The limbic system consists of; the hypothalamus which regulates homeostasis, the thalamus which has to do with sensory information except for smell, the amygdala which is active in producing aggressive behavior, the hippocampus is involved with our ability to remember new information. The frontal lobe is involved with voluntary muscle movements and also movements that have to do with learning, planning and emotions. The parietal is mainly involved with sensory sensations such as vision, hearing, and memory. The temporal lobe is mainly responsible for memory.
Without having structure and origination in the body existence would be lifeless. The body has so many complex structures that explanation could go on without an end. It’s remarkable how without even a thought our body works together.
