Chapter 9

Bacterial conjugation involves

A donor cell with a plasmid that synthesizes a pilus

Replication of DNA begins at a(n)

Adenine-thymine rich area

RNA molecules differ from DNA molecules because only RNA

All of the choices are correct

A screening system called the _____ test is used for detecting chemicals with carcinogenic potential.

Ames

Groups of 3 consecutive bases along the dna of a gene have the code for one

Amino acid

Of the following list, which antibiotics affect protein synthesis?

Both B and C ; penicillin and tetracycline

If a codon for alanine is GCA, then the anticodon is

CGU

Synthesis of a repressible enzyme is inhibited by

Co repressor and repressor binding to operator

The following pertain to ribosomes during protein synthesis except

Contain codons within their rRNA molecules

The enzymes that help pack DNA into the cell by coiling the DNA into a tight bundle are

DNA helicase

Okazaki fragments are attached to the growing end of the lagging strand by

DNA ligases

The enzyme that can proofread replicating DNA, detect incorrect bases, excise them and correctly replace them are

DNA polymerase

All mutations are not beneficial to the cell

False

DNA replication proceeds in one direction around the bacterial chromosome

False

Induced mutations result from errors in DNA replication

False

Introns have no detectable functions

False

Lactose is a co repressor in the lac operon

False

The smallest unit of heredity is a chromosome

False

The most serious type of mutation is a

Frame shift mutation

Each ______ is a specific segment of the DNA with the code for production of one functional product

Gene

The _______ is all of the genetic material of a cell

Genome

All of the following pertain to nitrogenous bases except

Guanine pairs with uracil

Which cell can transfer the most DNA?

Hfr cell

A nucleosome is a linear chromosome wound around the

Histone

Base pairs in DNA are held together by _______ bonds

Hydrogen

Which of the following is incorrect about transfer RNA?

Initiator tRNA in bacteria carries tryptophan

If the wild type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATA ETH EBI GRA T?

Insertion

A sequence of bases on a gene that does not code for protein is called an

Intron

lactose repressor

Is inactivated by binding lactose

Full induction of the lactose operon requires

Lactose present without glucose

The molecule is synthesized as a copy of a gene on the DNA template strand

Messenger RNA

If the wild type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATE THE BAG RAT?

Missense

Which of the following is not a type of bacterial DNA recombination?

Mitosis

permanent change in DNA

Mutations

All of the following pertain to RNA virus replication except

Negative-sense viruses directly undergo translation

If the wild type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATE (stop)?

Nonsense

The dna of microorganisms is made up of subunits called

Nucleotide

All of the following pertain to transcription except

Occurs on a ribosome in the cytoplasm

The expression of genetic traits is the

Phenotype

Hfr transfer involves all of the following except

Plasmid gene transfer

The nontranscribed region of DNA to which RNA polymerase binds to initiate transcription is called the

Promotor

A primer of ______ is needed at the origin of nucleotide addition

RNA

Which of the following additions have been made to principles of the central dogma of biology?

RNA can be used to regulate gene function

Gene regulation can involve a protein repressor that blocks ________ from initiating transcription

RNA polymerase

RNA polymerase binds to the

Regulation sequence

The opening segment composed of the gene that code for a protein depressor is called the

Regulators

duplication of DNA

Replication

Which of the following is incorrect about animal viruses?

Replication of viral rna occurs in the host nucleus

What type of mutation alters the base, but not the amino acid being coded for?

Silent

DNA gyrase

Super coils DNA

During replication, each parent DNA strand serves as a ________ for synthesis of new DNA strands

Template

Repressible operons require that ______ bind to the repressor protein before it can bind to the operator

The product

The rna that carry amino acids to the ribosomes during protein synthesis are called

Transfer RNA

Which of the following is not true of conjugation?

Transfer genes for a polysaccharide capsule

In griffiths experiments with streptococcus pneumonia, rough non-encapsulated streptococci were converted into smooth encapsulated streptococci in the presence of the heat-killed smooth encapsulated streptococci. What is the term that describes this process?

Transformation

The transfer of DNA fragments from a dead cell to a live, competent recipient cell that results in a charged recipient cell is

Transformation

The jumping of a gene from one location to another is done by

Transposons

3 base sequence on DNA

Triplet

DNA photolyase, in the presence of visible light, can repair DNA damage due to ultraviolet radiation

True

DNA polymerase can only add new nucleotides to the old 3' DNA end

True

Excised introns form structures called lariats

True

In bacteria, initiator tRNA carries formyl methionine

True

Repressible operons are normally turned on in the cell

True

Transcription occurs in the nucleus or at the nucleoid

True

split genes

Use spliceosomes to excise introns and then join exons

Semiconservative replication refers to

an original parent DNA strand and one newly synthesized DNA strand comprising a new DNA molecule.

Which of the following is not true of transposons?

are always part of plasmids

Which of the following is not true of an organism's genotype?

are the expressed traits governed by the genes

Structural genes code for

cellular proteins

A frameshift is caused by ______ mutations?

deletions and insertions

The process in which mutations are removed and the correct bases added is called

excision repair

A bacteriophage transfers DNA of the previous host to the current host. This is an example of

generalized transduction

Which is incorrect about inducible operons?

have genes turned off by a buildup of end product

Which of the following is incorrect about termination codons?

include AUG

A mutation that changes a normal codon to a stop codon is called a

nonsense mutation

The antiparallel arrangement within DNA molecules refers to

one helix strand that runs from the 5' to 3' direction and the other strand runs from the 3' to 5' direction.

Each nucleotide is composed of

one phosphate, one nitrogenous base, and one sugar

Which is incorrect about purines?

only found in DNA, not in RNA

DNA polymerase III

proofreads new DNA

DNA polymerase I

removes primers

The site where old DNA strands separate and new DNA strands will be synthesized is called the

replication fork

Which of the following is not associated with a prokaryotic ribosome

small unit provides the enzymes for making peptide bonds

The development of virulent, toxin-producing bacterial strains due to the presence of a temperate phage can occur in

specialized transduction

Synthesis of an inducible enzyme requires

substrate bound to repressor

DNA polymerase III

synthesizes new DNA only in the 5' to 3' direction

Which of the following is not a type of microRNA

tRNA

helicase

unwinds DNA