ABSTRACT
This chapter explores a survey of human anatomy and physiology, and the methods used to study the workings of the human organism for students with little background in biology. The nervous system is a complex communication system that receives information from its environment, makes decisions, and initiates responses in the form of muscular contractions and glandular secretions. The principle functional unit of the nervous system is the nerve cell or neuron. In the endocrine system the hormones are transported to various parts of the body where they influence the function of their 'target organs'. Hormones are 'informational molecules' carrying specific instructions to their target organs. The gastrointestinal system transports nutrients and fluids into the organism and transports wastes out; in between it accomplishes digestion and absorption of nutrients into the blood. The immune system defends the body against potentially harmful chemical toxins, cancer cells, and organisms such as bacteria and viruses.
