Student Center | Instructor Center | Information Center | Home

	Biocourse.com
	NetTutor
	Web Links
	Information on Anthrax
	Microbiology in the News
	Careers in Microbiology
	Study Tips
	Correlation Guide to MiM III
	Glossary A-F
	Glossary G-L
	Glossary M-R
	Glossary S-Z
	Clinical Case Studies
	Interactive Time Line
	Lab Sequence Data


	Chapter Overview
	Chapter Objectives
	Study Outline
	Chapter Web Links
	Web Exercises
	Flash Cards
	Self-Quiz
	True or False

	Feedback Help Center

Microbiology, 5/e

Lansing M Prescott, Augustana College
Donald A Klein, Colorado State University
John P Harley, Eastern Kentucky University

Genes: Expression and Regulation

Multiple Choice Quiz

Chooose the best answer


1	Which form of RNA acts as a blueprint for polypeptide biosynthesis by the ribosome?
		A)	mRNA
		B)	tRNA
		C)	rRNA


2	RNA is synthesized under the direction of DNA by this enzyme
		A)	DNA polymerase
		B)	DNA ligase
		C)	RNA polymerase


3	Which component of RNA polymerase facilitates the recognition of promoter sequences?
		A)	a subunit
		B)	b subunit
		C)	s subunit


4	The first hexameric sequence typically found in procaryotic promoters is located
		A)	at the transcription start site
		B)	approximately 35 bases upstream of the transcription start site
		C)	approximately 10 bases upstream of the transcription start site


5	What is the usual sequence of a Pribnow box?
		A)	TTGACA
		B)	TATAAT
		C)	UUUUUU


6	Following binding to a promoter, RNA polymerase next
		A)	unwinds a short segment of DNA
		B)	nicks one strand of DNA
		C)	begins to replicate DNA


7	Which of the following components is found in all procaryotic transcription terminators?
		A)	rho factor
		B)	a poly-U region
		C)	a hairpin structure


8	Posttranscriptional modification of RNA is more common in
		A)	procaryotes
		B)	eucaryotes


9	Which structure is found on eucaryotic mRNA but not procaryotic mRNA?
		A)	3' poly-A tail
		B)	5' cap


10	Which regions of interrupted genes code for RNA that will be present in the final RNA product?
		A)	introns
		B)	exons
		C)	promoter


11	What is a ribozyme?
		A)	a protein that synthesizes RNA
		B)	an RNA molecule that catalyzes a self-splicing reaction
		C)	a DNA molecule that acts as a template for RNA synthesis


12	What happens during amino acid activation?
		A)	a methyl group is attached to an amino acid
		B)	an amino acid is bound to mRNA
		C)	an amino acid is bound to tRNA


13	Which portion of a tRNA molecule is complementary to the mRNA triplet encoding a particular amino acid?
		A)	D arm
		B)	anticodon triplet
		C)	amino acid stem


14	Most procaryotic proteins begin with this modified amino acid
		A)	N-formylleucine
		B)	N-formylmethionine
		C)	N-formylserine


15	The most common initiator codon is
		A)	GUA
		B)	UAA
		C)	AUG


16	Which part of translation involves the addition of amino acids to an existing polypeptide chain?
		A)	initiation
		B)	elongation
		C)	termination


17	What molecule catalyzes the transpeptidation reaction?
		A)	peptidyl transferase
		B)	RNA polymerase
		C)	DNA ligase


18	Aminoacyl-tRNA binds to which site of the ribosome during elongation?
		A)	P site
		B)	A site
		C)	E site


19	Which of the following is NOT a nonsense codon?
		A)	AUG
		B)	UAA
		C)	UGA


20	What is the role of molecular chaperones?
		A)	to facilitate binding of ribosomes to mRNA
		B)	to degrade newly synthesized polypeptides that contain inaccurate sequences
		C)	to aid a newly synthesized polypeptide in folding to its proper shape


21	Many chaperones often are called ______________________ because of their expression under high temperatures.
		A)	heat-shock proteins
		B)	cold-shock proteins
		C)	thermostable protein


22	An enzyme whose amount is reduced by the presence of an end product are:
		A)	inducible enzymes
		B)	repressible enzymes
		C)	corepressors


23	A small molecule that causes the increase in levels of an inducible enzyme
		A)	repressor
		B)	corepressor
		C)	inducer


24	The operator is
		A)	another name for the terminator of a gene
		B)	a DNA site bound by repressor proteins
		C)	a protein that coordinates gene expression


25	The tryptophan operon in E.coli demonstrates a level of regulation called ______________ by the terminatation of transcription if tryptophan is abundant in cells.
		A)	activation
		B)	corepression
		C)	attenuation


26	Procaryotes have developed global regulatory systems
		A)	to aid in DNA replication
		B)	to regulate the regulation of many genes under varying environmental conditions
		C)	to determine the exact location of the cell on the globe


27	A collection of genes or operons that is controlled by a common regulatory proteins is called
		A)	a gene cluster
		B)	a genome
		C)	a regulon


28	A molecule of RNA that is complementary to a segment of another RNA molecule to which it will bind is called
		A)	antisense RNA
		B)	missense RNA
		C)	nonsense RNA


29	Which is not an essential part of a two-component phosphorelay system?
		A)	sensor kinase
		B)	response regulator
		C)	autoinducer

2002 McGraw-Hill Higher Education
Any use is subject to the Terms of Use and Privacy Policy.
McGraw-Hill Higher Education is one of the many fine businesses of The McGraw-Hill Companies.