What are the body systems?
The human body has many main organ systems that are necessary to fulfill their different functions. The most important body systems include the nervous system that controls and coordinate the body and includes the brain, spinal cord and nerves; the circulatory system that pumps blood throughout the body and includes heart, blood vessels and blood itself; and the respiratory system that regulates oxygen exchange and includes lungs, membrane, bronchi, larynx and trachea. The musculoskeletal system includes both bones and muscles and provides the human body support and structure, as well as the ability to move. Food nutrients are processed and absorbed by the digestive system, while the waste products are excreted in the digestive system and the urinary system. Other important body systems include the endocrine system, the immune system, the lymphatic system and the reproductive system.
Without a nervous system, the other system would have shut down. Using nerve cells called neurons the nervous system sends signals to different parts of the body, which triggers both the timeFloor, so involuntary reactions as contraction of voluntary muscle or heart beating. In humans and most other vertebrates, the central nervous system contains the brain and spinal cord that transmits signals to the nerve network in the rest of the body known as the peripheral nervous system.
Another vital system is a circulation system or more specifically a cardiovascular system that is the main mechanism of transport that carries gases, nutrients, hormones and blood cells throughout the body. One of the gases transported by the circulatory system is the oxygen that is obtained when blood is transmitted by lungs in a process called lung circulation. Oxygenation of blood is one of the primary functions of the respiratory system. Air inhalation is initiated by contractions of the diaphragm muscle, allowing the rib cage to expand and cause suction in the chest that pulls the air down into the lungs. Oxygen enters the bloodstream by diffuse via hollow anatomickThe structures in the lungs called alveoli, which also take carbon dioxide from the bloodstream, so it can be exhaled.
people gain energy by digesting food nutrients with another of the body systems, the digestive system. The digestion begins in the mouth, and the food breaks down by chewing and chemical effects of salivary glands. The chewed food called Bolus then swallows and travels through the esophagus on the way to the stomach, where stomach juices continue to decompose food molecules. Stomty waste travels through small and large intestines and are excreted in the form of feces. The urinary system is responsible for the excretion of liquid waste, with the kidneys filtering waste and secrete it into the bladder, where it is stored until it is excluded from the body in the form of urine.
Theendocrine system is a system primarily composed of hormonal glands. Hormones secreted by the endocrine system help to regulate the function of the body. Immune and lymphatic systems contribute to the defense of the human body by fighting the disease andby disposing of foreign substances and waste. The reproductive system includes the genital organs of men and women and its primary function is to produce descendants.