Aperson touches a hot surface with his hand and his hand springs back. which two systems are operating?

When  person touches a hot surface with his hand and his hand springs back. His nervous system and musculoskeletal system   is operating. 

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blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.