Pregunta 1
Pregunta
Which of the following is a major function of macrophages?
Respuesta
-
attacking cancerous cells
-
secreting antibodies
-
attacking cells infected by a virus
-
engulfing bacteria by phagocytosis
-
secreting cytokines to simulate the proliferation of other lymphocytes
Pregunta 2
Pregunta
Which of the following is a major function of cytotoxic T lymphocytes?
Respuesta
-
engulfing bacteria by phagocytosis
-
secreting antibodies
-
secreting cytokines to simulate the proliferation of other lymphocytes
-
attacking cancerous cells
-
attacking cells infected by a virus
Pregunta 3
Pregunta
Which of the following is a major function of B lymphocytes?
Respuesta
-
attacking cancerous cells
-
secreting cytokines to simulate the proliferation of other lymphocytes
-
secreting antibodies
-
attacking cells infected by a virus
-
engulfing bacteria by phagocytosis
Pregunta 4
Pregunta
Antibiotics (such as penicillin) are produced naturally by
Pregunta 5
Pregunta
An antibiotic (such as penicillin) works by
Respuesta
-
destroying all antigens present in the body
-
killing viruses only
-
killing both bacteria and viruses
-
killing bacteria only
-
neutralizing bacterial toxins
Pregunta 6
Pregunta
The main function of an antibody is to
Respuesta
-
initiate the destruction of bacteria
-
stimulate the proliferation of lymphocytes
-
destroy cells infected by a virus
-
destroy cancerous cells
-
engulf bacteria by phagocytosis
Pregunta 7
Pregunta
Which of the following is a true statement about bacteria?
Respuesta
-
bacteria are not affected by antibiotics
-
bacteria cause disease by reproducing inside of the body's cells
-
all bacteria that enter the human body are harmful
-
bacteria are harmful to the environment
-
bacteria cause disease by secreting toxins
Pregunta 8
Pregunta
Which of the following is a true statement about bacteria?
Respuesta
-
bacteria are not affected by antibiotics
-
there are many beneficial bacteria that live within the human body
-
bacteria are harmful to the environment
-
bacteria cause disease by reproducing inside of the body's cells
-
all bacteria that enter the human body are harmful
Pregunta 9
Pregunta
Which of the following is a true statement about bacteria?
Respuesta
-
Bacteria are not affected by antibiotics.
-
Bacteria cause disease by reproducing inside of the body's
cells.
-
All bacteria that enter the body are harmful.
-
Bacteria play an essential role in nature's chemical
recycling.
-
Most bacteria are harmful to the environment.
Pregunta 10
Pregunta
Which of the following is a true statement about plasmids?
Respuesta
-
They are found in bacteria, viruses and fungi.
-
They contain more genes than the bacterial
chromosome.
-
They enable some bacteria to become pathogens.
-
They prevent bacteria from mating with one another.
-
They are short, straight segments of DNA.
Pregunta 11
Pregunta
Which of the following is a true statement about plasmids?
Respuesta
-
They prevent bacteria from mating with one another.
-
They contain more genes than the bacterial
chromosome.
-
They are found in bacteria, viruses and fungi.
-
They enable some bacteria to resist antibiotics.
-
They are short, straight segments of DNA.
Pregunta 12
Pregunta
Which of the following is a true statement about plasmids?
Respuesta
-
They enable some bacteria to utilize rare
nutrients.
-
They prevent bacteria from mating with one
another.
-
They are found in bacteria, viruses and fungi.
-
They are short, straight segments of DNA.
-
They contain more genes than the bacterial
chromosome.
Pregunta 13
Pregunta
Mad cow disease is caused by
Respuesta
-
a virus that infects helper T lymphocytes.
-
a virus that infects neurons.
-
a prion that infects brain tissue.
-
a bacteria that weakens the immune
system.
-
a bacteria that infects brain tissue.
Pregunta 14
Pregunta
AIDS is a disease that is caused by
Respuesta
-
a prion that destroys lymphocytes.
-
a virus that infects helper T
lymphocytes.
-
a viroid.
-
a virus that infects B lymphocytes.
-
a bacteria that kills macrophages.
Pregunta 15
Respuesta
-
piece of RNA that infects plant
cells.
-
virus that infects helper T
lymphocytes.
-
virus that infects bacteria.
-
type of bacteria that lives in the
intestine.
-
protein that infects brain tissue.
Pregunta 16
Pregunta
Which of the following are found in a virus?
Pregunta 17
Pregunta
Viruses are not true cells because
Respuesta
-
They lack nucleic acids.
-
They cannot reproduce unless inside of a host
cell.
-
They are slightly smaller than prokaryotic cells.
-
They consist of one small piece of protein.
-
They cause human disease.
Pregunta 18
Pregunta
Which of the following happens when a RNAcontaining
virus infects a cell?
Respuesta
-
The host cell transcribes the viral DNA and produces new viral components.
-
The virus may cause Mad Cow disease.
-
The host cell uses the viral enzyme "reverse transcriptase" to make a copy of viral
DNA.
-
The virus becomes a symbiont of the cell.
-
The virus provides ATP for the cell.
Pregunta 19
Pregunta
Which of the following happens when a DNAcontaining
virus infects a cell?
Respuesta
-
The virus may cause Mad Cow disease.
-
The host cell uses the viral enzyme "reverse transcriptase" to make a copy of viral
DNA.
-
The virus provides ATP for the cell.
-
The virus becomes a symbiont of the cell.
-
The host cell transcribes the viral DNA and produces new viral components.
Pregunta 20
Pregunta
Which of the following best describes the enzyme "reverse transcriptase"?
Respuesta
-
It is an enzyme that RNA-viruses use to make the host cell copy DNA from viral
RNA.
-
It is a human enzyme used in metabolism.
-
It is a bacterial enzyme used in transcription of bacterial DNA.
-
It is an enzyme that DNA viruses use to make the host cell copy RNA from viral DNA.
-
It is an enzyme that host cells use to destroy viruses.
Pregunta 21
Pregunta
What is the purpose of restriction enzymes in nature?
Respuesta
-
They are used by fungi to kill bacteria.
-
They have no purpose in nature.
-
They are used by bacteria to prevent infection by viruses.
-
They are used by viruses to infect bacteria.
-
They are part of the human immune system.
Pregunta 22
Pregunta
How do biologists use restriction enzymes?
Respuesta
-
to cut DNA into thousands of 4nucleotide
fragments
-
to cut DNA at specific nucleotide sequences to produce DNA
fragments
-
none of these
-
to restrict the replication of DNA within cells
-
to cut RNA into several large fragments
Pregunta 23
Pregunta
What is the source of restriction enzymes?
Respuesta
-
They are manufactured in the laboratory.
-
They are obtained from fungi.
-
They are obtained from the human blood
stream.
-
They are obtained from bacteria.
-
They are obtained from viruses.
Pregunta 24
Pregunta
One reason for using restriction enzyme technology is
Respuesta
-
to treat human disease
-
to identify the location of specific genes
-
to predict the function of specific genes
-
to begin the process of DNA
fingerprinting
-
to identify the number of proteins in a cell
Pregunta 25
Pregunta
In the RFLP method of DNA fingerprinting, how are DNA fragments separated?
Pregunta 26
Pregunta
In a DNA fingerprint using the RFLP method, what forms the bands of the "fingerprint"?
Respuesta
-
Each band is a single DNA fragment of a different length.
-
Each band is a group of DNA fragments of a different size.
-
none of these
-
Each band is DNA from a different cell type.
-
Each band is a RNA fragment with a different nucleotide sequence.
Pregunta 27
Pregunta
Microarrays are used to
Respuesta
-
determine which genes have been expressed by a given cell
type
-
determine the nucleotide sequence of genes
-
none of these
-
determine whether mRNAs from a cell have been translated
-
determine which genes are present in the DNA of an organism
Pregunta 28
Pregunta
A cDNA probe is made by
Respuesta
-
none of these
-
using reverse transcriptase to copy mRNAs from the cytoplasm of
cells
-
using reverse transcriptase to copy DNA from the nucleus of cells
-
using fluorescent nucleotides to label RNA with cells
-
using reverse transcriptase to copy premRNAs
from the nucleus of cells
Pregunta 29
Pregunta
cDNA probes are used to
Respuesta
-
determine which pre-mRNAs are present within the nucleus of a cell
-
determine the nucleotide sequence of a given gene
-
determine which genes have been expressed by a cell
-
none of these
-
determine which genes are present within the nucleus of a cell
Pregunta 30
Respuesta
-
all types of RNA present within a cell
-
all of the proteins present within a
cell
-
all of the mRNA present within a cell
-
all of the genes present within a cell
-
none of these
Pregunta 31
Respuesta
-
none of these
-
all types of RNA present within a
cell
-
all of the mRNA present within a cell
-
all of the proteins present within a
cell
-
all of the genes present within a
cell
Pregunta 32
Pregunta
Which of the following is true of a cell's proteome?
Respuesta
-
It represents all of the proteins within a cell.
-
It is equivalent to the number of mRNAs within a
cell.
-
It includes all types of DNA and RNA within a cell.
-
none of these
-
It represents all of the genes within a cell.
Pregunta 33
Pregunta
Where is DNA located within plant cells?
Pregunta 34
Pregunta
Regarding extranuclear DNA, where is it located within eukaryotic cells?
Respuesta
-
within the nucleolus
-
within smooth and rough endoplasmic reticulum
-
within cytoplasmic ribosomes
-
within the cytoskeleton
-
within mitochondria and chloroplasts
Pregunta 35
Pregunta
What is the probable origin of extranuclear DNA in eukaryotes?
Respuesta
-
It is DNA that leaked out of the nucleus during evolution of eukaryotic cells.
-
It is the result of viral infections of eukaryotic cells.
-
none of these
-
It became part of the cytoskeletal structure of eukaryotic cells.
-
It was present in prokaryotes that became endosymbionts of eukaryotic
cells.
Pregunta 36
Pregunta
In current studies of human ancestry based on maternal inheritance, which of the following
approaches is used?
Respuesta
-
the entire genome is analyzed
-
mitochondrial DNA is analyzed
-
cDNA probes and microarrays are used
-
none of these
-
the entire proteome is analyzed
Pregunta 37
Pregunta
In eukaryotic organisms, mitochondrial DNA
Respuesta
-
is inherited only from the male parent
-
is not passed from parent to offspring
-
is inherited from both parents
-
is inherited only from the female parent
-
is only present if the offspring has been infected by a
virus
Pregunta 38
Pregunta
Analysis of human mitochondrial DNA can be use to determine
Respuesta
-
all of these
-
whether a person is related to a dead person
-
whether a person is related to another living person
-
in what region of the world a person's ancestors
lived
-
none of these
Pregunta 39
Pregunta
How can a researcher locate species that have genes which are homologous to a given human gene?
Respuesta
-
By using the computer program BLAST
-
none of these
-
By performing a microarray analysis
-
By using cDNA probes to locate mRNA
-
By determining the sequence of the human gene
Pregunta 40
Pregunta
How can the computer program BLAST be used?
Respuesta
-
To determine which genes are expressed in a cell by microarray analysis
-
To determine the amino acid sequence of a new protein by "protein
sequencing"
-
To locate genes of other species that are homologous to a known gene
-
all of these
-
To determine the nucleotide sequence of a new gene by "gene sequencing"
Pregunta 41
Pregunta
How can the computer program BLAST be used?
Respuesta
-
all of these
-
To determine which genes are expressed in a cell by microarray analysis
-
To determine the nucleotide sequence of a new gene by "gene sequencing"
-
To determine which animal species have proteins similar to a given human protein
based on amino acid sequence.
-
To determine the amino acid sequence of a new protein by "protein sequencing"
Pregunta 42
Pregunta
The human genome project determined that human DNA consists of
Respuesta
-
300,000 nucleotides
-
3 million nucleotides
-
3 million genes
-
3 billion proteins
-
3 billion nucelotides
Pregunta 43
Pregunta
What was the purpose of the human genome project?
Respuesta
-
To determine whether all humans have the same type of genes
-
To determine which genes are expressed in each type of human
cell
-
none of these
-
To determine the amino acid sequence of all proteins in human
cells
-
To determine the nucleotide sequence of all DNA in human cells
Pregunta 44
Pregunta
What was the source of DNA used in the human genome project?
Respuesta
-
DNA was obtained from 100 people who agreed to have their names published.
-
DNA was obtained anonymously from 100 people, but only a few samples were
used.
-
DNA was obtained anonymously from about 10,000 people and pooled.
-
DNA was obtained from several samples used in forensic investigations.
-
DNA was obtained from a single person--the man in charge of the project.