Chapter 6 Flashcards
_____ is a molecule that contains instructions for the functions of every cell and carries a record of evolutionary history.
a. DNA
b. ATP
c. Phosphate
d. Protein
e. Sugar
DNA
When regulatory proteins bind to an operator to block RNA polymerase, that is called ______. When regulatory proteins bind to an enhancer, that is called _____.
a. operator control; enhancer control
b. negative control; positive control
c. silencing; transcription
d. post-transcription regulation; pre-transcription regulation
e. epigenetics; methylation
negative control; positive control
What is the difference between a point mutation and a chromosomal aberration?
a. Point mutations occur at a specific point due to sunlight, whereas chromosomal aberrations can occur anywhere due to any type of DNA damage.
b. A chromosomal aberration is an all-inclusive term for any DNA mutation, and a point mutation is a type of aberration.
c. A chromosomal aberration is caused by DNA damage, while a point mutation is a mutation of a single base.
d. Both are mutation types, but in a point mutation, one base pair is changed, and in a chromosomal aberration, an entire section of the chromosome is altered.
e. Both are mutation types, but in a point mutation, the mutation occurs at a specific point anywhere on the chromosome. In a chromosomal aberration, the mutation is all throughout the chromosome.
Both are mutation types, but in a point mutation, one base pair is changed, and in a chromosomal aberration, an entire section of the chromosome is altered.
In DNA, which nitrogenous base pairs with adenine?
a. adenine
b. deoxyribose
c. guanine
d. cytosine
e. thymine
thymine
DNA is found in all of these organisms except _____.
a. humans
b. corn
c. apes
d. salamanders
e. DNA is found in all living organisms
DNA is found in all living organisms
RNA polymerase binds to the _______ of a gene to begin transcription.
a. intron
b. termination site
c. promoter site
d. operator
e. “stop” codon
promoter site
Most heritable human diseases are the result of mutations in _____ proteins, resulting in a toxic build-up of molecules.
a. enzymatic
b. regulatory
c. housekeeping
d. structural
e. operon
enzymatic
How is DNA organized in a human cell?
a. There are many strands, each consisting of 1 gene.
b. There are several strands, which are called genomes.
c. There is one circular loop of DNA.
d. There is one long strand of DNA.
e. There are 46 strands, called chromosomes.
There are 46 strands, called chromosomes.
The first step of transcription is:
a. DNA polymerase uses the information in DNA to create an mRNA transcript.
b. A transcript’s start sequence is recognized, and ribosomal subunits assemble.
c. RNA polymerase recognizes and binds to the gene’s promoter site.
d. RNA polymerase recognizes a promoter site and detaches from the DNA molecule.
e. A cap and tail are added to the transcript
RNA polymerase recognizes and binds to the gene’s promoter site.
Which statement is true concerning mutations and evolution?
a. Genes do not play a role in evolution.
b. Mutations increase fitness by producing effects that make individuals more likely to reproduce.
c. Mutations always result in the ability to outcompete competitors.
d. Mutations always cause disease and, therefore, thin out populations.
e. Mutations are a source of genetic variation.
Mutations are a source of genetic variation.
Most genes come in alternative forms called:
a. heterozygotes.
b. gametes.
c. homozygotes.
d. chromosomes.
e. alleles.
alleles.
- How many RNAs can be transcribed from a single DNA template?
a. Two RNAs per DNA template can be transcribed, because DNA is double-stranded.
b. Four RNAs, two per DNA strand, can be transcribed.
c. Only one RNA per DNA template can be transcribed.
d. It depends on the length of the DNA template strand.
e. Hundreds of RNAs can be transcribed from a single DNA template
Hundreds of RNAs can be transcribed from a single DNA template
Which statement about insertion, deletion, and substitution point mutations is true?
a. Insertion and deletion point mutations never change the sequence of amino acids in the polypeptide chain.
b. Insertion and deletion point mutations always shorten proteins.
c. Insertion and deletion point mutations alter the reading frame from the point of mutation to the end of the gene.
d. Substitution mutations always result in an amino acid substitution.
e. Substitution mutations can alter the reading frame from the point of mutation to the end of the gene.
Insertion and deletion point mutations alter the reading frame from the point of mutation to the end of the gene.
In DNA, which nitrogenous base pairs with adenine?
a. guanine
b. thymine
c. adenine
d. cytosine
e. deoxyribose
thymine
Which heritable disease is due to a mutation that causes nonfunctional enzymes, leading to a toxic build-up of molecules?
a. Cystic fibrosis
b. Color blindness
c. Breast cancer
d. Sickle cell anemia
e. Tay-Sachs disease
Tay-Sachs disease
What is the difference between a point mutation and a chromosomal aberration?
a. A chromosomal aberration is caused by DNA damage, while a point mutation is a mutation of a single base.
b. Both are mutation types, but in a point mutation, one base pair is changed, and in a chromosomal aberration, an entire section of the chromosome is altered.
c. Point mutations occur at a specific point due to sunlight, whereas chromosomal aberrations can occur anywhere due to any type of DNA damage.
d. Both are mutation types, but in a point mutation, the mutation occurs at a specific point anywhere on the chromosome. In a chromosomal aberration, the mutation is all throughout the chromosome.
e. A chromosomal aberration is an all-inclusive term for any DNA mutation, and a point mutation is a type of aberration.
Both are mutation types, but in a point mutation, one base pair is changed, and in a chromosomal aberration, an entire section of the chromosome is altered.
Which example is NOT a potential mutagen?
a. X rays
b. UV rays
c. lead aprons
d. cigarette smoke
e. engine exhaust
lead aprons
Chromosomal aberrations:
a. involves gene deletions or relocations, but not duplications.
b. are changes to the overall organization of genes on a chromosome.
c. are more harmful than point mutations.
d. occur when one base pair in the DNA is substituted for another.
e. occur when a base pair is inserted or deleted.
are changes to the overall organization of genes on a chromosome.
In eukaryotes, where can one find most of an organism’s DNA?
a. gametes
b. nucleus
c. cytoplasm
d. rough ER
e. Golgi apparatus
nucleus
The production of mRNA from DNA is called:
a. replication.
b. transcription.
c. transduction.
d. translation.
e. transformation.
transcription.
A mutation that involves the addition, subtraction, or substitution of a single base is known as:
a. genetic drift.
b. a point mutation.
c. a chromosomal aberration.
d. gene flow.
e. polyploidy.
a point mutation.
The three codons that do not code for any amino acid—UAA, UAG, and UGA—are also known as:
a. nonsense codons.
b. duplicate codons.
c. “start” codons.
d. “stop” codons.
e. transfer codons
“stop” codons.
These three stop sequences—UAA, UAG, and UGA—indicate the end of translation.
“stop” codons.
In _______ disease, lipids are not broken down within the lysosomes, resulting in cell death.
Tay-Sach
All of these scientists contributed to discovering the structure of DNA, except ______________.
a. Rosalind Franklin
b. Linus Pauling
c. James Watson
d. Charles Darwin
e. Francis Crick
Charles Darwin
The enzyme _____ recognizes and binds to the DNA molecule at the promoter site and unwinds it to begin reading the gene’s information.
RNA polymerase
In_____, DNA is found in the nucleus, the control center of each eukaryotic cell.
eukaryotes
RNA polymerase catalyzes the synthesis of:
a. RNA from DNA.
b. mRNA from tRNA.
c. DNA from RNA.
d. tRNA from mRNA.
e. DNA from DNA.
RNA from DNA.
In DNA, which nitrogenous base pairs with cytosine?
a. guanine
b. thymine
c. adenine
d. cytosine
e. deoxyribose
guanine
The steps of translation occur:
a. in the smooth endoplasmic reticulum.
b. on a ribosome in the cytoplasm.
c. on the plasma membrane.
d. in the nucleus.
e. in the Golgi apparatus.
on a ribosome in the cytoplasm.
Messenger RNA (mRNA) molecules are made during transcription in the_____. They leave the nucleus and travel to a ribosome in the_____, where the steps of translation occur.
nucleus; cytoplasm
