1. brain is the main organ of this system respiratory system 2. produces hormones endocrine system 3. breaks food down for body's use excretory system 4. sends nutrients to all the body's cells circulatory system 5. provides structure for the body nervous system 6. provides support and movement digestive system 7. kidneys are the main organs of this system muscular system 8. lungs are the primary organs of this system skeletal system

Which table best shows the impacts resulting from human activity? impact of human activities human activity impact forest area cleared to construct an airport increase in oxygen level vegetation cleared to construct an oil mine increase in pollution impact of human activities human activity impact forest area cleared to construct an airport increase in sound pollution vegetation cleared to construct a power plant contamination of water impact of human activities human activity impact beehives cleared from urban areas increase in vegetation dams constructed on a river increase in fish population impact of human activities human activity impact beehives cleared from urban areas increase in bird population dams constructed on a river better quality of water

How can you tell the difference between rough er from smooth er?

Facilitated diffusion move large molecules and/or polar molecules across the cell membrane. what does facilitated diffusion use to do this?