What are Purkinje fibers?
special valves that relay electrical impulses to
the ventricles, which cause contraction
special fibers that relay electrical impulses to
the atriums, which cause emptying
special valves that relay blood to the
ventricles, which cause contraction
special fibers that relay electrical impulses to
the ventricles, which cause contraction

Hey me with this one❤❤❤❤ every organism needs food. does a cell also need it? explain very briefly.

Which statement about dna replication is true? a. eukaryotes only have one circular chromosome that unwinds at multiple locations. b. eukaryotes can only replicate one segment of a chromosome at a time. c. prokaryotes can only replicate their single circular chromosome in the nucleus. d. prokaryotes only have one origin of replication to initiate replication.

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.