In humans and other organisms, Which substance plays a central role as an energy sourse? A. water
B. carbs
C. fat
D. protien

Which statement best describes the relationship between an allele and a gene? question 1 a. an allele is a variation of a gene that can be expressed as a phenotype. b. an allele is the part of a gene that attaches to messenger rna molecules. c. an allele is a segment of a dna molecule that controls replication of a gene.

How can active reading strategies you? o a. they can you get into better physical shape. o b. they can you read fewer science articles. o c. they can you understand what you read. o d. they can you avoid reading altogether.

The main ingredient of magma is a pahoehoe. b silca c dissolved gases d obsidian