This system covers the body. Skin protects against germs and injury. Hair and nails are also part of the coverings of the body. Skin helps control body temperature. It also allows you to feel things.
Integumentary System
This system is made of the cardiovascular and lymphatic. It moves blood around the body. The heart pumps blood and blood carries oxygen and nutrients to cells. It also removes waste products. This system keeps all parts of the body alive and working.
Circulatory System
Integumentary
- hair
- nails
Circulatory
- heart
- blood vessels
This system gives the body its shape and support. Bones protect important organs. The skull protects the brain. Bones work with muscle to create movement. Bone marrow makes blood cells.
Skeletal System
This system helps you breathe. Air enters through your nose or mouth. The lungs take the oxygen from the air. Carbon dioxide leaves your body when you exhale. This system works closely with the circulatory system.
Respiratory System
Skeletal
- skull
- bones
Respiratory
- lungs
- trachea
This system allows movement. Muscles pull on bones to help you move. Some muscles work on their own. The heart is also a muscle. Exercising helps keep the muscles strong.
Muscular System
This system breaks down food. Food is chewed by your mouth first so you don't choke. The stomach uses acids to help digest food. Nutrients are absorbed in the small intestine. The body uses nutrients for energy and growth.
Digestive System
Muscular
- biceps
- triceps
Digestive
- stomach
- small intestine
This system controls everything your body does. The brain sends messages through the nerves. The spinal chord helps carry signals to and from the brain. It helps you think, feel, and move. This system reacts quickly to danger or changes.
Nervous System
This system removes liquid waste from the body. Kidneys filter waste from the blood. Extra water becomes urine. The bladder stores urine until it leaves the body. This system helps keep body chemicals balanced.
Urinary System
Nervous
- brain
- spinal cord
Urinary
- bladder
- kidneys
This system uses hormones to control body functions. Hormones travel through the bloodstream. They control growth and development. It also helps control mood and energy levels. It works slowly but has long-lasting effects.
Endocrine System
This system allows humans to have babies. It produces special cells needed for reproduction. In females, ovaries make eggs. In males, testes make sperm cells. This system also controls changes during puberty.
Reproductive System
Endocrine
- pituitary gland
- thyroid gland
Reproductive
- ovaries
- testes