Which is the most likely reason that stem cell research is controversial?
Stem cell research could lead to the development of human clones.
Many people assume that all human stem cells come from embryos.
Research by using stem cells results in high-priced treatments for disease.
Information that is obtained from stem cell research is considered unreliable.

Answer

Many people assume that all human stem cells come from embryos.

Explanation:

Not all stem cells are embryonic stem cells. In fact, a lot of stem cell type procedures come from stem cells in bone marrow. The controversy behind embryonic stem cells is that they come from aborted babies, which many don't agree with.

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.