Grade 1 Sample Lesson Plan: Unit 6 – My Body- The Brain

16. The vessels that carries oxygen-rich blood into the heart muscle is. called . 17. A group of cells that receives messages about the body’s oxygen needs. and sends out signals to adjust the heart rate is called the . 18. At the site of a wound, platelets set off reactions that eventually cause. the production of a chemical called . 19. ................
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