DNA replication always proceeds in only one direction because the ________ of the incoming nucleotide is attached to the free ________ of the growing DNA strand.
A) 5'-phosphate / 3'-hydroxyl
B) 3'-phosphate / 5'-hydroxyl
C) 5'-deoxyribose / 3'-base
D) 3'-base / 5'-deoxyribose
The precursor of each new nucleotide in a strand of DNA is a
A) deoxynucleoside 5'-diphosphate.
B) deoxynucleoside 3'-diphosphate.
C) deoxynucleoside 5'-triphosphate.
D) deoxynucleoside 3'-triphosphate.
Many pharmaceutical drugs specifically inhibit transcription in Bacteria but not Archaea or Eukarya. Why would drugs that inhibit transcription only affect Bacteria and not Archaea even though they are both prokaryotes?
A) Archaea and Eukarya have very similar ribosomes that are different than bacterial ribosomes.
B) Bacteria lack a nucleus.
C) Archaea lack operons.
D) Archaea and Eukarya have very similar RNA polymerases that are different than bacterial RNA polymerases.
Genes that encoded for polymerases, gyrases, ribosomal proteins, and other proteins essential to replication, transcription, and translation are present on
A) chromosomes.
B) plasmids.
C) chromosomes and plasmids.
D) neither chromosomes nor plasmids.
How are plasmids different than chromosomes?
A) Plasmids are always small, linear pieces of DNA.
B) Plasmids are composed of single-stranded DNA.
C) Plasmids contain genes that are NOT essential for cellular growth and replication.
D) Plasmids carry unimportant genes that are of little significance for the ecology and metabolism of an organism.