Micro Final- Ch 7 HW

Genes are active in a region of the eukaryotic chromosome called

heterochromatin.
the plasmid.
euchromatin.
the nucleoid.
the histone.

euchromatin

Which of the following is found at the 5 end of a DNA strand?

a phosphate group
a hydroxyl group
histones
a methyl group
a hydrogen bond

a phosphate group

A plasmid might be found in all of the following types of cells EXCEPT:

protozoan cells.
fungal cells.
animal cells.
prokaryotic cells.

animal cells

The bacterial chromosome is

usually circular.
found in a nucleoid.
found in a nucleus.
both circular and found in a nucleoid.
both circular and found in a nucleus.

both circular and found in a nucleoid

Semiconservative DNA replication means that

-the cell can proofread its newly synthesized DNA only part of the time.
-each strand of a double-stranded DNA molecule is replicated differently.
-the sequence of a DNA molecule is preserved as it is being replicated.
-each daughter DNA molecule is composed of one original strand and one new strand.
-nucleotides are constantly being recycled as cells make DNA.

each daughter DNA molecule is composed of one original strand and one new strand.

Which of the following types of plasmids allows a bacterial cell to kill its competitors?

resistance factors
bacteriocin factors
cryptic plasmids
virulence factors
fertility factors

bacteriocin factors

Which of the following must be removed from a eukaryotic mRNA molecule before it can be translated?

exon
promoter
codon
anticodon
intron

intron

Which of the following is NOT involved in the regulation of the lac operon?

cyclic AMP
an inducer
an iRNA
a repressor protein
glucose

an iRNA

Which of the following processes is involved in the "central dogma" of genetics?

DNA replication
DNA replication and translation
transcription and translation
translation
transcription

transcription and translation

The Ames test proves that a chemical is

mutagenic in Salmonella.
mutagenic in humans.
carcinogenic.
carcinogenic in humans.
carcinogenic in Salmonella.

mutagenic in Salmonella.

What is considered to be the average natural mutation rate that occurs during DNA replication?

One in every trillion nucleotides replicated.
One in every million nucleotides replicated.
One in every billion nucleotides replicated.
One in every ten thousand nucleotides replicated.

One in every billion nucleotides replicated

A mutation that affects the genotype of the organism but not the phenotype is called a

missense mutation.
silent mutation.
nonsense mutation.
frameshift mutation.

silent mutation

A base insertion or deletion in the translated region of the gene may lead to

nonsense mutation.
silent mutation.
missense mutation.
frameshift mutation.

frameshift mutation

A base substitution that changes a codon coding for an amino acid to a stop codon is called a

silent mutation.
nonsense mutation.
frameshift mutation.
missense mutation

nonsense mutation

How frequently do silent mutations occur?

One out of every billion mutations
One out of every three mutations
Half of all mutations
One out of every million mutations

One out of every three mutations

The process of making a complementary copy of DNA into the form of RNA is called __________.

translation
transformation
transduction
transcription

transcription

Which of these is NOT a difference between eukaryotic and bacterial gene expression?

-Bacteria have 70S ribosomes, while eukaryotes have 80S ribosomes in their cytoplasm.
-Bacteria may have genes organized and regulated within operons, while eukaryotes lack operons.
-Initiation of translation in bacteria occurs when the ribosomal subunit binds to the 5′ guanine cap, while in eukaryotes it binds to a specific nucleotide sequence.
-Eukaryotic RNA is modified prior to translation, whereas bacterial RNA is not

Initiation of translation in bacteria occurs when the ribosomal subunit binds to the 5′ guanine cap, while in eukaryotes it binds to a specific nucleotide sequence. *The reverse is true. Eukaryotic ribosomes bind to the 5′ guanine cap, while bacterial ribosomes bind to a specific nucleotide sequence called the ribosome binding site.

Which of the following events occurs during transcription?

-A molecule of RNA is formed based on the sequence of nucleotides in DNA.
-A cap is added to the RNA molecule.
-The message in mRNA is translated into a protein.
-mRNA binds to a ribosome in the cytoplasm.
-Those segments of the RNA strand that do not actually code for the protein are removed.

A molecule of RNA is formed based on the sequence of nucleotides in DNA.

Which of the following is a correct statement about mRNA?

-mRNA moves from the nucleus to the cytoplasm following RNA processing.
-mRNA binds directly to amino acids during translation.
-mRNA is transcribed from DNA in the cytoplasm.
-mRNA includes a cap that consists of extra adenine nucleotides.
-Segments of mRNA that code for protein are removed before translation.

mRNA moves from the nucleus to the cytoplasm following RNA processing

The site of translation is

the cell nucleus.
ribosomes in the cell cytoplasm.
the Golgi apparatus.
the plasma membrane.
ribosomes in the cell nucleus.

ribosomes in the cell cytoplasm

Which one of the following does not play a role in translation?

Ribosomes
tRNA
Anticodon
Amino acids
DNA

DNA

Which of the following does not occur during RNA processing?

-mRNA attaches to the small subunit of a ribosome.
-Segments of the RNA strand that do not actually code for the protein are removed.
-Segments of RNA that do code for the protein are reconnected.
-A modified guanine nucleotide is added to the beginning of the RNA strand as a cap.
-Adenine nucleotides are added to the end of the RNA strand, forming a tail.

mRNA attaches to the small subunit of a ribosome.

What is the function of the conjugation pilus?

It contains an F plasmid.
It converts F- cells into F+ cells.
It carries the chromosome of F- cells.
It pulls the F+ and F- cells together.

It pulls the F+ and F- cells together

What is required by an F- cell to become an F+ cell?

Conjugation pilus
F plasmid
An F- cell to be a recipient
F+ chromosome

F plasmid

What is the key difference between donor cells and recipient cells?

A chromosome
An F plasmid
Size
Cell membranes

An F plasmid

What cellular macromolecule is the fertility factor comprised of?

Protein
Nucleic acid
Carbohydrate
Lipid

Nucleic acid

At which point does a recipient cell become an F+ cell?

1. Fusion of the cell membranes
2. Attachment of the sex pilus
3. Transfer of the single stranded F factor
4. Pulling of donor and recipient cells together
5. Formation of the complementary strand of the F factor

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