Parts modified to perform a single function in combination with other parts performing the same function , in whole they are like a large organ divided in to different shapes and tissues to coordinate together.
Brings air into and out of the lungs to absorb oxygen and remove carbon dioxide.
Circulates blood around the body via the heart, arteries and veins, delivering oxygen and nutrients to organs and cells and carrying their waste products away. Keeps the body's temperature in a safe range.
System to absorb nutrients and remove waste via the gastrointestinal tract, including the mouth, esophagus, stomach and intestines. Eliminates waste from the body.
Defends the body against pathogens that may harm the body. The system comprising a network of lymphatic vessels that carry a clear fluid called lymph.
The system where the kidneys filter blood to produce urine, and get rid of waste.
The reproductive organs required for the production of offspring.
Main article: Male reproductive system
Collects and processes information from the senses via nerves and the brain and tells the muscles to contract to cause physical actions.
See also: List of nerves of the human body