Dramatic changes in sea level occurred throughout the cenozoic era and the rise and fall of sea level is recorded in the rocks of the amazing numbers of fossil clams, snails, and sand dollars can be found in these marine rocks, along with fossilized whale bones and shark teeth.

The rate at which molecules water and oxygen can enter a cell is determined by the-

For a comparative or experimental investigation, scientists often make a testable about a scientific question, and then they test it in the investigation. a.control b.hypothesis c.procedure d.system

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.