Anatomy and Physiology Organ Systems

Anatomy and Physiology

Organ systems are "composed of two or more different organs that work together to provide a common function," (Carpi 1999). Among the most important organ systems in the body are the integumentary, skeletal, muscular, nervous, senses and endocrine systems. None of these systems are any more important than any other, as all are crucial for the harmonious functioning of the human body.

The integumentary organ system consists of the skin and its related parts including follicles and hair as well as the sebaceous glands. The skin is the largest organ of the body, and comprises up to 15% of total body weight. Underlying tissues including fat can be considered part of the integumentary system.

Both the skeletal and muscular system enable bodily movement. The skeletal system provides the form and structural support for that movement, while the muscular system provides the "pulling power for us to move around," ("Muscular System" n.d.). Muscles and bones are physically connected, making the muscular and skeletal systems literally inseparable.

The nervous system is among the more complex in the body because it can potentially control most of the other organ systems in the body. The nervous system includes the brain and spinal cord and its cells are highly specialized. Input from sensory organs and from the skin is transmitted via the nervous system. In fact, the sensory system "is a part of nervous system consisting of sensory receptors that receive stimuli from internal and external environment, neural pathways that conduct this information to brain and parts of brain that processes this information," ("Sensory Systems" n.d.). The endocrine system also works in tandem with the nervous system to send messages throughout the body. Via various glands in the body, the endocrine system specializes in chemical and hormonal regulation.

2. The nervous system controls many other organ systems and functions in the body and is therefore central to the organism's survival. Moreover, the nervous system is like a control center for the other organ systems in the body, facilitating communication between them. The nervous system accomplishes its tasks via a network of specialized cells and organs such as the brain.

The brain works in tandem with the spinal cord to send messages throughout the body. The nervous system is aided by the endocrine system, which produces chemicals like hormones used to send messages to various organs and body parts. However, the nervous system also uses electrical impulses to help carry chemicals like those secreted by the endocrine system. The nervous system could not function properly without the endocrine system, and vice-versa.

Smooth muscles are the main part of the muscular system that is controlled by the nervous system. Part of the autonomic, or independent, nervous system, the smooth muscle system helps to regulate those bodily functions we cannot readily control via self-will such as digestion. However, all muscles are ultimately controlled by the central nervous system. Because the muscles are attached to the skeleton, all skeletal movements can be traced back to the central nervous system. The integumentary system is one of the body's primary interfaces with the outside world. Together with the sensory system, the integumentary system interact with the central nervous system by communicating its inputs.

3. Homeostasis is the body's state of equilibrium, achieved via self-regulation. A state of homeostasis is best described as feeling "normal," when the organism is not cold, tired, hungry, frightened, or sick with disease. All the organ systems are implicated in the creation and maintenance of homeostasis. Each organ system specializes in some aspect of the body's ability to create and maintain homeostasis.

External forces such as viruses, bacteria, or sensory stimulation may upset the body's homeostasis. Thoughts and psychological processes can also affect homeostasis, which is why the mind and body are connected. The interface between mind and body is perceptible mainly in the nervous system but biofeedback and other tools reveal ways in which the mind and emotions impact other organ systems directly.