There are only 20 amino acids used in all species on Earth with very little variation. What might scientists conclude from this?

Glucose is broken down in different ways, both in the presence and in the absence of oxygen. using the table for reference, what major products are formed in each reaction set?

The bacteria inside a tube worm would be analogous to what organism in the ocean ecosystem near the waters surface? a. photosynthetic algae b. shrimp c. clown fish d. parasitic lamprey

Natural resources are any materials that humans obtain from the earth to meet our wants and needs.