Dna, rna, and starch: what do these three important biomolecules have in common?

What does polymerase chain reaction (pcr) do? o a. separates dna fragments by size o b. cuts a dna sample into fragments o c. provides an overall picture of a person's chromosomes o d. makes more copies of a sample of dna

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm

Which of the following explains why a tree is often used as a model to represent the principle of common descent