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5.5. The smallest cell in the world is:

Which kind of aquatic ecosystem does the photograph most likely show? a. marsh b. swamp c. lake d. river

An organ system consists of a group of organs that performs specific functions necessary for the survival of an organism. humans have eleven different organ systems: integumentary, skeletal, muscular, nervous, endocrine, circulatory, lymphatic, respiratory, digestive, urinary, and reproductive. discuss the function of neurons, the brain and the spinal cord within the human nervous system while explaining the interrelationship of each organ.

Explain how scientists use geologic time to determine the age of landforms.