The diversity of proteins in humans is primarily a result of: a) the existence of 5' caps and 3' poly-a tails. b) the large size differences in mrna transcripts. c) exon variability in mature mrna. d) the vast number of genes compared to other eukaryotic organisms. polycistronic mrnas.

hammurabi rulers

good lesson

that scientist would be robert hooke

the nitrogen cycle provides nitrogen to the ecosystem from the atmosphere, ground and oceans. nitrogen is an important component of complex molecules such as amino acids and nucleotides, which lead to the creation of proteins and dna, the building blocks of all life. plants absorb nitrogen in the form of ammonium, nitrate ion and, on rare occasions, as amino acids. animals receive nitrogen necessary for biological processes from feeding on living or dead organic matter.