The Human Body
- Circulatory system: Blood circulations with heart and blood vessels.
- Digestive system: Processing food with mouth, stomach and intestines.
- Endocrine system: Communicating within the body using hormones.
- Immune system: Defending against disease-causing agents.
- Integumentary system: Skin, hair and nails.
- Lymphatic system: Structures involved in the transfer of lymph between tissues and the blood stream.
- Muscular system: Moving the body.
- Nervous system: Collecting, transferring and processing information with brain and nerves.
- Reproductive system: The sex organs.
- Respiratory system: The organs used for breathing, the lungs.
- Skeletal system: Structural support and protection through bones.
- Urinary system: The kidneys and associated structures involved in the production and excretion of urine.
Links to Related Fields of Study 
Extraordinary care must be taken while studying human body for the purpose of treatment or education, etc. There are many extraordinarily yet importantly sophisticated natural systems which make up the whole human body. A few examples are the skeletal system, the muscular system, respiratory system, the reproductive system, the digestive system, the nervous system, the blood circulatory system, the urinary system, etc. The various systems consist of different organs and/or limbs which have specific functions. For example digestive system consists of hands, mouth, tongue, teeth, inner throat, stomach, small intestine, large intestine, etc. There are many parts of human body, namely: head, neck, shoulders, chest, arms, back, abdomin, buttock, legs, feet, etc. Health of every organ, limb or system is important. However, the health of some organs is vital for survival as that of heart, brain, liver, lungs, etc. Physical, psychological, mental and spiritual healths are inter-related and interdependant.