Genetics and genetic engineering (Chapter 9& 10)

Transcription involves initiation,_____________ , and termination.

Elongation

In eukaryotes, which DNA sequences encode functional protein?

Exons

A codon contains how many nucleotides?

3

How many stop codons are contained within the genetic code?

3

Which template DNA sequence encodes the peptide sequence phenylalanine-leucine-aspartic acid-valine? (Look up the genetic code figure in your textbook)

3'-AAAAACCTACAT-5'

The mRNA chain is built in the ______ direction.

5' to 3'

R factors are specifically associated with which mechanism of recombination?

Conjugation

A(n) ______ is a sequence of DNA nucleotides that codes for one functional protein or RNA.

Gene

The enzyme involved in replicating a new DNA strand is DNA polymerase _____, and DNA polymerase _____ is involved in removing the RNA primer, closing gaps, and repairing mismatched bases.

III, I

True or false: A point mutation results from an insertion or deletion of nucleotides, and always leads to a shift of the triplet sequence from the point of mutation downstream.

False

True or false: DNA polymerase converts DNA into the various types of RNA during transcription.

False

True or false: Mutations are always harmful to cells.

False

True or false: Viral genomes are always composed of either single or double stranded DNA.

False

Which type of plasmids confer the ability of an organism to survive treatment by antibiotics?

R factors

During transcription, RNA polymerase synthesizes ______ from a(n) ______ template.

RNA; DNA

Which term refers to the transfer of genes from donor to recipient microorganisms?

Recombination

Which are parts of the lactose operon?

Regulator Control locus Structural locus

_________________operons often contain genes coding for anabolic enzymes and are usually turned off by the end product of the reactions catalyzed by these enzymes.

Repressible

_________mutations in DNA are caused by random mistakes in replication and not known to be influenced by any mutagenic agent.

Spontaneous

Which type of mutation is due to random mistakes in replication?

Spontaneous mutation

The __________codon AUG of mRNA is associated with the tRNA anticodon UAC and the amino acid methionine.

Start

True or false: R-factors or "resistance factors" can be shared between bacteria through conjugation to help them survive the effects of antibiotics.

True

True or false: Several codons code for the same amino acid, which is called the redundancy of the code.

True

________,___________ ,_____________ and are the three stop codons within the genetic code.

UAA, UAG, UGA

Nucleotide is to nucleic acid as______ _________ is to protein.

amino acids

Plasmids are found in which type(s) of organisms?

bacteria and fungi

Which recombination method involves transfer of DNA via bacteriophages?

Transduction

Which gene transfer method involves the uptake of free DNA by competent bacterial cells?

Transformation

True or false: A mutation is an alteration in the DNA sequence or content of a cell that is passed on when the cell divides.

True

True or false: During DNA replication, both the leading and lagging strands are synthesized in the 5' to 3' direction.

True

Unlike DNA, RNA contains the nitrogenous base

Uracil

True or false: During protein synthesis, many copies of a specific protein can be synthesized from a single mRNA transcript.

True

Any nitrogen-containing molecule found in DNA and RNA that provides the basis for the genetic code is a nitrogenous _____________.

base

Any nitrogen-containing molecule found in DNA and RNA that provides the basis for the genetic code is a nitrogenous____________.

base

Which best describes the antiparallel orientation of strands in DNA?

One strand is 5' to 3' and the other is 3' to 5'.

A(n) _____________is the specific sequence of 3 mRNA nucleotides, based on a DNA triplet, that encodes a particular amino acid.

codon

A bacterial cell described as_________ can accept soluble DNA from the surrounding environment.

competent

_______in bacteria refers to horizontal gene transmission via pili.

conjugation

The lactose operon is composed of the regulator, the ______ locus, and the structural locus.

control

Which of the following is NOT a type of RNA?

dRNA

The DNA of a chromosome is single double______________-stranded.

double

In _____, chromosomes are wound twice around histone proteins, creating a chain of nucleosomes. Multiple choice question.

eukaryotes

Proteins that remove incorrect bases and replace them with correct ones are termed ______ repair enzymes.

excision

___________are DNA sequences which encode for functional proteins.

exons

What is the inducer of the lactose operon?

lactose

The newly forming DNA strand that is discontinuously replicated in segments (Okazaki fragments) is called the ___________strand.

lagging

Which strand is replicated discontinuously in segments during DNA replication?

lagging

The _____________, or continuous, strand is replicated without segments during DNA replication.

leading

Which strand is replicated continuously without segments during DNA replication?

leading strands

The final sealing of nicks in a newly synthesized DNA strand is catalyzed by the enzyme_________ .

ligase

Which enzyme completes the final sealing of nicks in a newly synthesized DNA strand?

ligase

Which molecule contains the codons for the polypeptide?

mRNA

During eukaryotic protein synthesis, ______ ribosome(s) are used to translate mRNA that contains ______ gene(s).

many, one

The three types of RNA are___________ RNA, ____________RNA, and ______________RNA.

messenger, ribosomal, transfer

The__________ bases are either purines or pyrimidines.

nitrogenous

A ______ mutation results in early termination of the protein.

nonsense

a _______mutation changes an amino-acid-producing codon into a stop codon, leading to premature termination of a protein.

nonsense

What is the result of a point mutation that changes a template gene sequence from 3'-TACGCCATATAT-5' to 3'-TACGCCATCTAT-5'?

nonsense mutation

A _______________is the basic unit of DNA structure.

nucleotide

The basic unit of DNA structure is the

nucleotide

The replication ________________is the Y-shaped point on a replicating DNA molecule where the DNA polymerase is synthesizing new strands of DNA.

fork

A(n)__________ mutation results from an insertion or deletion of nucleotides in multiples of 1 or 2, leading to a shift of the triplet sequence from the point of mutation downstream.

frameshift

_____________mutations are generally most harmful to cells because they cause the greatest change in the amino acid sequence of a protein.

frameshift

The science of heredity is called _______.

genetics

The complete set of chromosomes and genes in an organism is referred to as the

genome

The_______________ is the sum of all the genes constituting an organism's distinctive genetic makeup.

genotype

An organism's genetic makeup is referred to as its ____________, whereas the expression of those genes is referred to as the organism's______________ .

genotype, phenotype

The entire genetic makeup of an organism is its _______, but the expression of certain genetic traits are known as its _________.

genotype, phenotype

The enzyme _____________unzips the DNA helix prior to the start of replication.

helicase

Which enzyme unzips the DNA helix prior to the start of replication?

helicase

A ________ serves as the vector for transduction in bacteria.

phage

Mutations that involve the addition, deletion or substitution of one or a few bases are referred to as _______ mutations.

point

Mutations that involve the addition, deletion or substitution of no more than a few bases are referred to as____

point mutation

Donor and recipient bacterial cells are connected by the sex _________during conjugation.

pilus

The ____________of the genetic code results in several codons encoding the same amino acid.

redundancy

During semiconservative______________ the DNA is duplicated prior to binary fission.

replication

DNA ________synthesizes DNA strands in the 5' to 3' direction.

polymerase

What must occur prior to cell division to ensure that each new cell has a complete set of DNA chromosome(s)?

replication

During _________________DNA replication, the newly made double helices are composed of one parent template and one newly synthesized strand.

semiconservative

__________operons often contain genes coding for anabolic enzymes and are usually turned off by the end product of the reactions catalyzed by these enzymes.

repressible

The protein product of a repressor gene is the_______ which binds the operator to stop transcription. Listen to the complete question

repressor

The__________ protein is capable of repressing an operon.

repressor

Two subunits of the____________ come together to perform protein synthesis.

ribosomes

The mRNA sequence AUG, specifying the first amino acid in protein sequences, is called the

start codon

In DNA, adenine pairs with _____________, whereas cytosine pairs with ___________________.

thymine, guanine

The term___________ , or codon, is a sequence of 3 nucleotides in DNA that encodes an amino acid.

triplets

In a chromosome, the DNA is composed of ______ strands.

two

The nitrogenous base thymine is only found in DNA, while ________ is only found in RNA.

uracil

Which nitrogenous base is found in RNA but not found in DNA?

uracil

The native or _____ type strain exhibits nonmutated characteristics.

wild

A special type of RNA called _______ removes introns from eukaryotic mRNA sequences.

spliceosomes

Which is a purine?

Guanine

Which term refers to an organism that has a mutation?

Mutant

Which type of RNA comprises ribosomal subunits?

rRNA

Which DOES NOT occur during translation elongation?

-enzymatic breaking of bond between tRNA and polypeptide chain -formyl methionine is delivered to the ribosome

In protein synthesis, eukaryotic and prokaryotic cells show similarities in all of the following EXCEPT the

-number of proteins encoded on a single mRNA. -use of formyl-methionine as the first amino acid.

Which occurs during translation elongation?

-tRNA delivers amino acid to empty A site -formation of peptide bond between amino acids in A and P sites -translocation of ribosome

Which is the correct order of events in transcription?

1. initiation 2. elongation 3. termination

How many replication forks are formed from opening a section of a circular DNA molecule during replication?

2

What is the main effect of ultraviolet radiation on DNA?

Abnormal bonding between adjacent pyrimidines

The nitrogenous bases found in DNA include:

Adenine, Guanine, Thymine, Cytosine

Which type of RNA is transcribed from a DNA template?

All types of RNA

The_______ test is used to determine the carcinogenic potential of a chemical.

Ames

Plasmids can be found in both _______ and ____

Bacteria, fungi

Which is true regarding adenine and guanine?

Both are purines

What is the function of tRNA?

Brings amino acids to the ribosome

The genome of a prokaryotic or eukaryotic cell includes DNA found in which sites?

Chloroplasts Chromosomes Mitochondria Plasmids

A____________ is a discrete cellular structure composed of a neatly packaged DNA molecule.

Chromosome

During which method of gene transfer are bacterial cells in direct contact?

Conjugation

Eukaryotic chromosomes are composed of _____.

DNA

Genes are made up of ______, a macromolecule made up of nucleotides.

DNA

The "blueprint" information for the production of proteins is permanently encoded in sections of

DNA

The genome of a cell is entirely composed of the macromolecule known as ______.

DNA

What determines the order of amino acids in the primary structure of a protein?

DNA sequence of a gene

What is the name of the specialized plasmid that directs conjugation in gram-negative cells?

F factor

________is the study of the inheritance of living things.

Genetics

Which term represents all of the genetic information within a cell?

Genome

The ______ is the genetic makeup of an organism that is ultimately responsible for an organism's expressed characteristics.

Genotype

Genetic inheritance in microorganisms is best defined by which term?

Heredity

___________is another term for genetics--the study of inheritance in living things.

Heredity

DNA polymerase ____ is the main enzyme involved in the building of the new DNA chain, whereas DNA polymerase ____ is involved mostly with removing the primers and repairing damaged DNA.

III/I

Where are the chromosomes of yeast cells located?

In the nucleus

What type of DNA mutation occurs as a consequence of exposure to chemical or physical mutagens?

Induced

________________operons are usually turned on by the substrate of the enzyme for which the structural genes code.

Inducible

After a eukaryotic mRNA has been transcribed, _______ are removed.

Introns

Which DNA sequences are found within a gene but do not encode the protein specified by that gene?

Introns

__________are DNA sequences found within a gene that do not encode the protein corresponding to the gene.

Introns

What amino acid sequence is encoded by the DNA template sequence 3'-TACCGCGCTCTACCG-5'?

Methionine-Alanine-Arginine-Aspartic Acid-Glycine

Which type of mutation results in a different amino acid being incorporated into a protein?

Missense

A DNA nucleotide is composed of a(n)__________________ , a(n) __________sugar, and a(n)_______________ base.

Nitrogenous base Deoxyribose sugar Phosphate

Which of the following are parts of a nucleotide in DNA?

Nitrogenous base Deoxyribose sugar Phosphate

Which mutation changes an amino acid producing codon into a stop codon?

Nonsense

In a protozoal or fungal cell, chromosomes are located in the

Nucleus

In replication of DNA, the lagging strand is replicated in a discontinuous manner forming________________ fragments.

Okazaki

__________________fragments are formed during DNA replication of the lagging strand.

Okazaki

The characteristics resulting from the interaction of the particular genetic makeup of an organism and the environment is the________________ of that organism.

Phenotype

The expression of the genotype creates traits referred to as the

Phenotype

Which process repairs DNA that has been damaged by ultraviolet radiation using visible light?

Photoactivation

What is a small circular segment of DNA found in the cytoplasm of prokaryotes that is capable of independent replication and usually contains nonessential genes?

Plasmid

a ____________is a small circular segment of DNA found in the cytoplasm of bacteria that is capable of independent replication and usually contains nonessential genes.

Plasmid

Which organic molecule is formed from chains of amino acids?

Protein

How does RNA differ from DNA in bacteria and eukaryotes?

RNA is single-stranded In RNA, uracil replaces thymine

The main enzyme responsible for transcription is

RNA polymerase

Which of the following are functions of RNA polymerase?

Synthesizes an RNA molecule from DNA template Unwinds the DNA so that transcription can take place

The complementary sequence to 5'-AAGTC-3' is 3'-______-5'.

TTCAG

If one strand of DNA reads 5'-AAGCGTTA-3', the complementary sequence would be 3'-_______-5'.

TTCGCAAT

If one strand of DNA reads 5'-AAGCGTTA-3', the complementary sequence would be 3'-__________________-5'.

TTCGCAAT

Which of the following describes the primary structure of a protein?

The chain of amino acids bound by peptide bonds

What is the purpose of the Ames test?

To determine the carcinogenic potential of a chemical

____________is the process of decoding DNA into messenger RNA.

Transcription

Which term, synonymous with codon, describes a trinucleotide sequence coding an amino acid in DNA?

Triplet

In DNA, the two strands of the helix are arranged in _____________orientation.

antiparallel

Lactose acts as an _____________in the lactose operon.

inducer

Lactose acts as an__________ in the lactose operon.

inducer

A ________mutation results in a different amino acid being incorporated into a protein, with varying results.

missence

An agent that induces changes in DNA is a(n)

mutagen

Which is an agent that induces changes in DNA?

mutagen

An organism that has a mutation is called a

mutant

A permanent inheritable alteration in the DNA sequence of a cell is a(n)

mutation

The specific order of amino acids bound to each other by peptide bonds represents the ____________structure of a protein.

primary

During replication initiation, the enzyme__________________ synthesizes primer sequences.

primase

Which enzyme synthesizes primer sequences during replication initiation?

primase

In _____ a special enzyme called a topoisomerase coils a chromosome into a tight bundle.

prokaryotes

During protein synthesis, many copies of a specific____________ can be synthesized from a single mRNA transcript.

protein

The DNA blueprint specifies how to make what type of macromolecule?

proteins

______ are functional biomolecules in cells formed from one or more long chains of amino acids.

proteins

In DNA, a purine always combines with

pyrimidine

The main effect of ultraviolet radiation on DNA is abnormal bonding between adjacent ________.

pyrimidines

The prokaryotic ribosome is composed of ______ and protein.

rRNA

_______ RNA brings the amino acids to the ribosome.

transfer

The ribosome, composed of rRNA and protein, is involved in the process of

translation