Rna contains the nitrogenous base instead of which is only found in dna.

Which of the following will not cause mass extinction? a. drastic change is weather b. geological change c. both a and b d. none of the above

Amutagen is 1: a living thing that has undergone a mutation. 2: an agent that causes a mutation in dna. 3: a mutation that has affected one gene. 4: a chemical that can poison living cells.

What can be said about farmers in highly developed countries? a) they have little or no negative impact on the environment. b) they practice subsistence agriculture. c) they are able to incorporate polyculture into their farming practices. d) they utilize organic farming techniques on a regular basis. e) they rely on large amounts of energy from fossil fuels.