Which gas did volcanoes not produce in the precambrian era?
o
a. oxygen
o
b. sulfur
o
c. water vapor
o
d. carbon dioxde

Melting glaciers is a serious threat to the environment what is the possible consequence of melting glaciers on polar bears?

One of the purposes of transcription is to produce a sequence of bases that

Which of these is not an example of molecular homology? 1. use of dna and rna as genetic material 2.use of glycolysis as the first step in cellular respiration in both plants and animals 3. the lack of an igf-1 gene in prokaryotes 4. the use of aldolase b to break down fructose in bacteria, plants and animals