There are 10 body systems, one of them is the Integumentary (skin). It is composed of hair, skin, nails, sense receptions and oil glands. Its functionis to protect from outside, to regulate the body temperature, to make synthesis of hormones & chemicals and is used as a sense organ.
Another one is the Skeletal System (bones). It is made of about 206 bones, that are divided in tho categories: axial bones (in the body by itself) and apendicular bones (arms & legs). We have Joints too. Thei`re divided in Ball
Socket (like elbow and shoulders) and sattle (fingers). This system`s function are movement, storage of minerals, blood formation, support of the body and protection of body parts. The next one is the Muscular System. It is composed of muscles (dah). The muscles are divided in visceral or involuntary or smooth (The one in the organs, like intestines), skeletal or voluntary or striated (found superficial to the bones, like biceps, triceps...) and cardiac (heart). Their functions are movement, to maintain body posture & tone and in the production of body heat.
Now its time for the Nervous System. Its constructed of the brain, the spinal cord and the nerves (neurons). Its functions are to communicate (fast with short duration), integration, and to control. The subsequent system is the Endocrine
System (known as ductless too...). This is composed of a lot of things... They are:pituitary gland - below the brain (master gland), pineal gland - brain (It`s called the "third eye" by some, because its sensitive to light cycles), hypothalamus - also in the brain (it works with the pituitary), the thyrodic - neck (controls the metabolism), adrenal - kidneys (responsible for the adrenaline), pancreas - near stomach (produces insulin), ovaries - on females and testes - on males (it produces estrogen and ova - testosterone and sperm, respectively). Their functions are to secrete hormones into the blood, communication (slow & long duration), integration and