Enzyme which seals dna fragments together
b. chemical mutagen
c. type of mutation that produces a reading frameshift
d. substance which induces change in dna bases
e. method by which dna is copied at cell division f. a change in dna base sequence g. procedure to screen chemicals for mutagenic properties h. closed circular dna, with few genes, non-essential to the cell i. chemicals produced by bacteria which kill other bacteria