The amount of nitrogen in the atmosphere is affected by: a. sewage treatment plants b. inorganic nitrogen fertilizers c. pollution from factories d. all of the above

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

How does the study of genetic disorders such as pku biologists understand normal alleles?

What substance is the most acidic. lemon juice. tomato juice. sodium hydroxide. water