Human Systems

Nervous System

The nervous system is the system whose objective is controls everything you do, including breathing, walking, thinking, and feeling.

IMPORTANT PARTS: brain

Respiratory System

The respiratory system is how we breathe in oxygen and breathe out carbon dioxide. Oxygen is a gas that we need to live, and carbon dioxide is a waste product that our body makes when we use oxygen.

IMPORTANT ORGAN: lungs

Reproductive System

The reproductive system is how boys and girls can make babies when they grow up. Boys have a reproductive system that makes sperm, and girls have a reproductive system that makes ovaries.

IMPORTANT PARTS: penis, vagina

Circulatory System

The circulatory system is how our body moves blood around to all parts of our body. Blood is really important because it carries oxygen and nutrients that our body needs to grow and stay healthy.

IMPORTANT ORGANS: heart

Digestive System

The digestive system is the way our body breaks down food that we eat into smaller pieces, so that our body can use the nutrients and energy from the food to help us grow, play and stay healthy.

IMPORTANT ORGANS: stomach, intestine