試題詳解

21. DNA replication is said to be semiconservative because_________.
(A)the number of nucleotides within genes remains constant
(B)half of the DNA in a cell comes from one parent and the other half from the other parent.
(C)the same process of DNA replication is used by all organisms
(D)the total amount of DNA within an individual remains the same
(E) cach new DNA molecule is composed of one old strand and one new strand