| A | B |
|---|
| respiratory system | oxygen enters body and CO2 exits |
| circulatory system | transports blood throughout the body |
| skeletal system | provides support and protection for animals |
| lymphatic system | includes immune system to defend from illnesses |
| endocrine system | releases hormones into the blood to control activities of cells. |
| digestive system | processes food and liquid taken in by the organism and prepares it for use by the body |
| nervous system | detects and responds to external and internal stimuli |
| muscular system | allows animals to move and change shape |
| integumentary system | protects the body from the external environment (controls temperature, flow of blood/water) |
| urinary system | helps keep amounts of fluids and materials balanced. removes waste |
| reproductive system | consists of the organs necessary for animals to produce offspring |
