What happens right before transcription begins? a. mrna is produced from nucleic acids. b. the transcription process stops. c. dna is produced from the mrna. d. rna polymerase is guided to the correct place?

Transcription is the transfer of genetic information from DNA to RNA, and it happens in the nucleus.  We can automatically rule out B.  B is incorrect because it doesn't make sense; how can a process stop before it even begins?

A.  I believe this is incorrect because mRNA is involved when the genetic information needs to leave the nucleus.  mRNA would take it to a ribosome outside of a nucleus.  Since transcription happens in the nucleus, mRNA is irrelevant before it starts.

C.  This doesn't really make sense.  mRNA carries information from the DNA, but not vice versa (in these early stages).

D.  This would make the most sense, since RNA polymerase needs to attach to the promoter on the strand before transcription can begin.

Mitochondria produce atp, a high energy compound. atp is used for all sorts of enzyme-mediated reactions, such as making proteins/nucleotides/etc, certain compounds cross the cell membrane, muscles move, etc.  without this source of energy, a cell will die. it will not be able to repair itself, defend against pathogens, etc.