How many nitrogenous bases are there? what are the name?

Explain why gene expression may be decreased when histones are deacetylated/DNA is methylated.

Phosphorus is? A. found freely in the atmosphere B. returned to the soil by rhizoblum C. added to the soil through weathering D. usually very abundant in an ecosystem

Name four impotant biogeochemical processes that cycle nutrients

Greatest dissolved solid in ocean water?

What are proteins used for in living things?

Which of the following is NOT mentioned as an important role of soil? O Filtering water O Supporting organisms Filtering air O Providing nutrients to plants

What is the difference between a reactant and a product?

Choose the definition of: Vertebrates A. Having no backbone B. have a backbone C. having several backbones D. having lost a backbone

Describe the process digestion of mouth

Which cell on the graphic organizer is also the structure that allows the virus to enter the host cell?