Inside the Human Body Brought To You By Extremebodyworkout P90X Workout

The human body consists of a number of systems that can perform various functions to facilitate the movements, growth, and sustenance of a human being. When all the major systems are in good condition, a person will experience good health, and he or she can perform a wide range of tasks.

• How the Body Works
• Tour of the Human Body

Skeletal System

The skeleton is comprised of bones that are joined together to keep the human body in shape. Without the skeleton, the human body will be just a lump of tissue and blood on the ground. The skeletal system does not only enable a human being to move; it also provides protection for important organs such as the heart, the lungs, and the brain. An adult human being has approximately 206 bones in his or her body, and these bones are held together by ligaments. There is a tough and shiny coating called cartilage at the end of each bone, and the bones are separated at the joints by a film of fluid that controls friction between bones.

• The Skeletal System
• Diagram of Skeletal System
• Skeletal System

Respiratory System

The respiratory system facilitates breathing, which is essential for the survival of a human being. During the process of respiration, the body will take in oxygen and let out carbon dioxide. When air comes through the nose or the mouth, it passes through the trachea, and it is channeled into the two bronchi. It will then enter the lungs, where it will be further divided by smaller tubes known as bronchiolies. There are alveoli attached to the ends of the bronchiolies, and these small balloons will work with capillaries to filter the air, so that oxygen will be released into the bloodstream and carbon dioxide will be retained for exhalation.

• Human Respiratory System
• Respiratory System Diagram
• Amazing Facts about the Respiratory System

Nervous System

The nervous system is made up of a network of cells that can provide information about a human being’s surroundings as well as occurrences within his or her own body. It comprises of neurons as well as glial cells, which work together to create impulses within and between the central nervous system and the peripheral nervous system. The peripheral nervous system contains sensory neurons that will respond to stimuli by sending signals to the central nervous system. The latter will then process and deliver signals to the glands and muscles, and this will result in a human being’s reaction to stimuli.

• How Does the Nervous System Work?
• Nervous System Diagram
• Central Nervous System

Muscular System

The muscular system’s main function is to facilitate the movement of the human body. There are over 650 different muscles in the body, and these muscles are divided into three types, namely, the skeletal, cardiac, and the smooth muscles. All muscles are attached to bones, and they respond to signals from the nervous system by expanding and contracting, which will in turn cause certain parts of the human body to move.

• Muscular System Diagram
• The Muscular System
• Muscular System Quiz

Digestive System

The digestive system works to break down food, so that it will become small enough to be released into the bloodstream. The entire digestive system in a human body measures about nine meters long. The process of digesting food starts when a person breaks down food with his or her teeth and mouth. The food is softened with saliva, and it is swallowed and channeled to the stomach via the esophagus. It is further broken down with acid in the stomach, and it is transported to the small intestines, where it undergoes further digestion. Digested food will enter the bloodstream, and undigested food will be transported to the rectum and anus for removal.

• The Digestive System and How it Works
• Digestive System Diagrams
• Chemistry of the Digestive System

Circulatory System

The circulatory system transports blood to various organs throughout the human body, so that these organs will receive sufficient supplies of oxygen and nutrients. The heart is the organ that pumps blood and keeps the circulatory system running. Blood will be pumped out from the left side of the heart, and it will go through the arteries before it is channeled into capillaries, where oxygen and food are distributed to cells and waste materials and carbon dioxide are taken into the bloodstream. The blood will then be transported through veins, and it will end up in the right side of the heart, where it will be pumped into the lungs. Carbon dioxide will be replaced by oxygen in the lungs, and the blood will travel to the left side of the heart.

• The Circulatory System
• Diagram of Human Circulatory System
• Circulatory System