Which of these are NOT principal steps in "gene expression"? a) Transcription b) RNA processing c) Translation d) DNA replication Answer: D--- DNA Replication In eukaryotes, the newly transcribed RNA usually undergoes chemical processing in the: a) nucleus. b) cytosol. c) rough endoplasmic reticulum. d) Golgi apparatus. Answer: A--- Nucleus In the process of gene expression, the protein made is called the: a) gene product. b) transcript. c) cistron. d) exon. Answer: A—Gene Product Polypeptide by the action of ribosomes. Which end of the new polypeptide emerges from the ribosome first (i.e., which end is made first)? a) amino b) carboxyl c) 5’ d) 3’ Answer: A---amino Polypeptide chains are synthesized by the addition of successive amino acids to the __________ terminus of the growing chain. a) amino b) carboxyl c) 5’ d) 3’ Answer: B----Carboxyl In a newly translated protein, a Methionine is always found at this end. a) C terminus, but only in eukaryotes. b) N terminus, but only in eukaryotes. c) C terminus in both prokaryotes and eukaryotes. d) N terminus in both prokaryotes and eukaryotes. Answer: D--- N terminus in both prokaryotes and eukaryotes In eukaryotes, transcription of rRNAs is mediated by: a) RNA polymerase I b) RNA polymerase II c) RNA polymerase III d) RNA polymerase IV Answer: a---RNA Polymerase I
The following statements are true for DNA replication. Which is not true for transcription? a) A single-stranded DNA template is needed. b) A polymerase is needed. c) Nucleotides are added that are complementary to the template DNA. d) Nucleotides are added only to the 3’ end of a growing nucleotide chain. e) A 3’ end of a primer sequence is needed. f) Incorrectly added nucleotides are eliminated by 3’ exonuclease. g) Original DNA template is permanently separated. h) The polymerase proofreads as it adds bases. Answer: E F G H Most polypeptide chains have regions that can independently fold upon themselves to form well-defined structures; these folding units are called: a) cistrons. b) domains. c) open reading frames. d) parasegment . Answer: B--- domains RNA polymerase binds to DNA wherever the DNA has a particular site called a(n): a) Shine-Dalgarno sequence. b) AUG codon. c) operator. d) origin of replication. e) promoter. f) enhancer. Answer: E---- promoter In molecular genetics, a promoter is an attachment site for a(n): a) DNA polymerase. b) RNA polymerase. c) ribosome. d) transcriptional activator protein. Answer: b----RNA Polymerase Which of these is a property of RNA polymerase? a) High processivity. b) Ability to remain on DNA template until termination sequence is reached. c) 3’ exonuclease activity.