Muscular System: The brain uses the nerves to tell the muscles when to move. The nerves also deliver information on what to do in a fight or flight case. Respiratory System: The brain sends pulses through the nerves to the lungs which tell them to move to collect and release oxygen and carbon dioxide.

Just as the organs in an organ system work together to accomplish their task, so the different organ systems also cooperate to keep the body running. For example, the respiratory system and the circulatory system work closely together to deliver oxygen to cells and to get rid of the carbon dioxide the cells produce.

Homeostasis refers to the body’s ability to maintain a stable internal environment (regulating hormones, body temp., water balance, etc.). Control centers in the brain play roles in regulating physiological parameters and keeping them within the normal range.

Each organ system performs specific functions for the body, and each organ system is typically studied independently. However, the organ systems also work together to help the body maintain homeostasis. For example, the cardiovascular, urinary, and lymphatic systems all help the body control water balance.

Hormones are responsible for key homeostatic processes including control of blood glucose levels and control of blood pressure. Homeostasis is the regulation of the internal conditions within cells and whole organisms such as temperature, water, and sugar levels.

The nervous system is the major controlling, regulatory, and communicating system in the body. It is the center of all mental activity including thought, learning, and memory. Together with the endocrine system, the nervous system is responsible for regulating and maintaining homeostasis.

The nervous system helps all the parts of the body to communicate with each other. It also reacts to changes both outside and inside the body. The nervous system uses both electrical and chemical means to send and receive messages.

The nervous system plays a role in nearly every aspect of our health and well-being. It guides everyday activities such as waking up; automatic activities such as breathing; and complex processes such as thinking, reading, remembering, and feeling emotions. The nervous system controls: Brain growth and development.

Functions of the Nervous System The nervous system has 3 main functions: sensory, integration, and motor.

The nervous system has three broad functions: sensory input, information processing, and motor output. In the PNS, sensory receptor neurons respond to physical stimuli in our environment, like touch or temperature, and send signals that inform the CNS of the state of the body and the external environment.

The four main functions of the nervous system are:

• Control of body’s internal environment to maintain ‘homeostasis’ An example of this is the regulation of body temperature.
• Programming of spinal cord reflexes. An example of this is the stretch reflex.
• Memory and learning.
• Voluntary control of movement.

The Central Nervous System is the integration and command center of the body. It consists of the brain, spinal cord and the retinas of the eyes. The Peripheral Nervous System consists of sensory neurons, ganglia (clusters of neurons) and nerves that connect the central nervous system to arms, hands, legs and feet.

The nervous system is involved in receiving information about the environment around us (sensation) and generating responses to that information (motor responses). The nervous system can be divided into regions that are responsible for sensation (sensory functions) and for the response (motor functions).

Disorders of the nervous system may involve the following: Vascular disorders, such as stroke, transient ischemic attack (TIA), subarachnoid hemorrhage, subdural hemorrhage and hematoma, and extradural hemorrhage. Infections, such as meningitis, encephalitis, polio, and epidural abscess.

Examples include:

• Parkinson’s disease.
• Multiple sclerosis (MS).
• Amyotrophic lateral sclerosis (ALS).
• Alzheimer’s disease.
• Huntington’s disease.
• Peripheral neuropathies.

Neurologists specialize in studying and treating the brain and nervous system. They diagnose and treat problems that include Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, stroke, amyotrophic lateral sclerosis (ALS), epilepsy, migraine, and concussion.