Which best explains the importance of pH in determining the health of a water system? A. Most organisms living in water are able to adapt to changing water pH. B. Variations in the pH of water can indicate the presence of toxic substances.
C. A low pH in ground water encourages the growth of photosynthetic organisms.
D. Variations in the pH of water can affect the ability of water to absorb atmospheric gases.

Read the sentence. “yesterday we arrived late for the outdoor concert in the city gardens.” which words in the sentence are adverbs? a. late; city b. yesterday; outdoor c. yesterday; late d. outdoor; city

Connection compare and contrast genetic engineering to the process of natural selection. select all statements that are true.

The blue particles in this image are able to cross the cell membrane through simple diffusion. how will they be transported? outside the cell inside the cell o a. the substances will move directly across the membrane from outside the cell to inside the cell. b. the substances will move through channels in the membrane proteins from outside the cell to inside the cell. o c. the substances will move through channels in the membrane proteins from inside the cell to outside the cell. o d. the substances will move directly across the membrane from inside the cell to outside the cell.