The brain controls the contraction of skeletal muscle. The nervous system regulates heart rate and the speed at which food moves through the digestive tract. The endocrine system secretes hormones into blood and other body fluids. These chemicals are important for metabolism, growth, water and mineral balance, and the response to stress. Pineal body, pituitary gland, hypothalamus, thyroid, parathyroid, heart, adrenal gland, kidney, pancreas, stomach, intestines, ovary Hormones provide feedback to the brain to affect neural processing.
Reproductive hormones affect the development of the nervous system.
The hypothalamus controls the pituitary gland and other endocrine glands. The lymphatic system protects the body from infection. The brain can stimulate defense mechanisms against infection. The respiratory system supplies oxygen to the blood and removes carbon dioxide. Lungs, larynx, pharynx, trachea, bronchi The brain monitors respiratory volume and blood gas levels.