Animals with radial symmetry have embryos (blastula) with: A. two germ layers, the ectoderm and the endoderm.
B. no germ layers as they free-form.
C. three germ layers, the ectoderm, the mesoderm and the endoderm.
D. one germ layer.
E. None of these.

c.) polymerase chain reaction

- "unlike the original dna fingerprinting method, dna profiling does not use restriction enzymes to cut the dna. instead it uses the polymerase chain reaction (pcr)? to produce many copies of specific str sequences. pcr is an automated procedure that generates lots of copies of a specific sequence of dna."

mathematical model hope this