Deck 11: How Genes Are Controlled

Question 1

Non-coding DNA sequences are referred to as ________.

A)exons
B)introns
C)genes

Answer 1

A

Question 2

Which is a type of post-transcriptional regulation of gene expression?

A)inactivation of tRNA
B)alteration of DNA nucleotide sequences
C)breakdown of proteins
D)binding of transcription factors to enhancers

Answer 2

C

Question 3

The process by which genotype becomes expressed as phenotype is ________.

A)gene regulation
B)transcription
C)gene expression
D)translation

Answer 3

C

Question 4

Cells communicate with one another via ________.

A)cascades of gene activation
B)the diffusion of RNA transcripts through adhesion junctions
C)signal transduction pathways
D)RNA splicing

Question 5

In prokaryotes, the production of a single RNA transcript for a group of related genes is under the control of ________.

A)an operon
B)enhancers
C)a signal transduction pathway
D)transcription factors

Question 6

What would you assume if you found RNA transcripts of lactose-utilizing genes within E. coli?

A)Lactose has bound to the lac operon activator.
B)Lactose is present in the cell.
C)The lac operon activator protein is present in the cell.
D)The lac operon repressor protein is absent in the cell.

Question 7

Homeotic genes are important for ________.

A)the development of an organism's body plan
B)gene expression in prokaryotes
C)signal transduction pathways
D)gene regulation in eukaryotic cells

Question 8

Bacterial RNA polymerase binds to the ________.

A)operator
B)repressor
C)enhancer
D)promoter

Question 9

What would enable a single RNA transcript to be translated into different polypeptides?

A)The RNA transcript can be spliced more than one way.
B)The coded polypeptide may be modified in more than one way.
C)The length of the RNA transcript tail can vary.
D)Two different genes can produce the same RNA transcript, which will then be translated differently.

Question 10

In bacteria, what name is given to a cluster of genes with related functions, along with their DNA control sequences?

A)operon
B)operator
C)promoter
D)repressor

Question 11

What is the first level of control of eukaryotic gene transcription?

A)RNA splicing
B)attachment of RNA polymerase to the promoter
C)DNA packing and unpacking
D)the binding and unbinding of transcription factors to enhancer sequences

Question 12

Repressors act by blocking the binding of ________ to the operator.

A)promoters
B)DNA polymerase
C)the operon
D)RNA polymerase

Question 13

Male tortoiseshell cats ________.

A)do not have an X chromosome
B)have orange and black patches of fur that reflect the pattern of X chromosome inactivation
C)are usually XYY individuals
D)are likely to be exceedingly rare and very likely to be sterile since normal male cats are XY

Question 14

In an operon, the ________ acts as an on/off switch.

A)operator
B)promoter
C)activator
D)repressor

Question 15

Which is most likely to cause the development of a six-legged frog?

A)mutation of homeotic genes
B)binding of repressors to operons
C)a mutation in DNA polymerase that affects all cells
D)conversion of a proto-oncogene to an oncogene

Question 16

In a eukaryotic cell an abnormal protein is binding to the promoter for a gene. Which process will likely occur in this scenario?

A)Transcription factors will bind to enhancers.
B)Transcription factors will bind to the promoter.
C)The gene will be expressed normally.
D)RNA polymerase will bind to the promoter.

Question 17

What type of protein binds to silencers to prevent gene expression from occurring?

A)enhancers
B)repressors
C)promoters
D)RNA polymerase

Question 18

Which of these plays a role in the regulation of transcription in both prokaryotic and eukaryotic cells?

A)RNA splicing
B)attachment of RNA polymerase to the promoter
C)transcription factors
D)gene operons

Question 19

What is the function of a repressor protein?

A)To turn off transcription by binding to the operator.
B)To turn off transcription by binding to the activator.
C)To turn on transcription by binding to the operator.
D)To turn on transcription by binding to the activator.

Question 20

While examining a human cell that functions normally, you determine that it has 45 functional chromosomes and one chromosome that is almost completely inactive. You immediately decide that it is very likely that this cell ________.

A)came from a normal human female
B)is lacking a chromosome
C)is a gamete
D)will become cancerous if one or two more genes are mutated

Question 21

What is the benefit of using avatars in cancer treatments?

A)Avatars result in the cure for cancer.
B)Avatars allow clinicians to identify more effective drugs to use.
C)Avatars can be used to prevent the onset of cancer in young people.
D)Avatars are used to develop new drugs to treat cancer.

Question 22

About one out of how many women will develop breast cancer?

A)2
B)4
C)8
D)10

Question 23

When referring to cell division, oncogenes are most like ________ while tumor suppressor genes are most like ________.

A)the brakes on a car; the gas pedal on a car
B)the gas pedal on a car; the brakes on a car
C)the steering wheel on a car; the gas pedal on a car
D)the brakes on a car; the steering wheel on a car

Question 24

More people die of ________ cancer than of any other cancer.

A)lung
B)skin
C)pancreatic
D)breast

Question 25

Suppose a cDNA has the sequence CTTAGGA. What is the corresponding mRNA sequence?

A)AGGATTC
B)GAATCCT
C)GAAUCCU
D)UCCUAAG

Question 26

Which risk factor is associated with cancer of the colon and rectum?

A)tobacco
B)viruses
C)UV radiation
D)dietary fat

Question 27

Data suggest that the normal version of BRCA1 functions as a(n)________.

A)oncogene
B)tumor-suppressor gene
C)proto-oncogene
D)silencer

Question 28

Many proto-oncogenes regulate ________.

A)cell growth
B)cell cloning
C)cell division
D)cell repair

Question 29

Inheritance of certain genes increases the risk of getting certain cancers; thus, it can be said that ________.

A)these cancers are inherited as a dominant trait
B)mutations that occur in somatic cells can be passed from parent to offspring
C)predisposition to these cancers is inherited
D)lifestyle will have little impact on cancer risk for these individuals

Question 30

Which of these lifestyle choices will increase cancer risk?

A)jogging
B)spending less time in the sun
C)changing to a diet low in plant fiber
D)quitting smoking

Question 31

Reproductive cloning has many applications. Choose the exception.

A)the production of genetically identical mice and rats for scientific use
B)the production of organs in pigs for transplant into humans
C)creating stem cells to treat human diseases
D)restoring populations of extinct animals such as the saber-toothed tiger

Question 32

If you were working for a pharmaceutical company trying to develop anticancer drugs, what biological process would be the best target to investigate?

A)meiosis
B)mitosis
C)cellular respiration
D)glycolysis

Question 33

Homeotic genes ________.

A)have very different sequences in plant cells as compared to animal cells
B)are an example of convergent evolution
C)are evidence of the common ancestry of eukaryotic organisms
D)regulate gene expression in both prokaryotic and eukaryotic cells

Question 34

How are the cells in different body tissues able to perform different functions?

A)The cells exhibit different patterns of gene expression.
B)Different chromosomes have been inactivated in different cells.
C)The cells contain different genes.
D)Mutations have accumulated in the cells over time.

Question 35

How can mature plants be cloned to produce genetically identical copies?

A)Mature plant cells contain only a fraction of the genes found in an adult plant.
B)Plants have evolved over time to suit the need of human agriculture.
C)Mature plant cells can develop into all the specialized cells of an adult plant.

Question 36

________ is(are)responsible for more cancers than any other carcinogen.

A)asbestos
B)UV radiation
C)tobacco
D)X-rays

Question 37

What name is given to a gene that causes cancer?

A)repressor
B)promoter
C)homeotic gene
D)oncogene

Question 38

Which technique could tell you how gene expression differs between individuals with and without cystic fibrosis?

A)therapeutic cloning
B)DNA microarray
C)reproductive cloning

Question 39

Tumor cells can change over time in a variety of ways. The following options are all ways that tumors change over time except for one. Choose the exception.

A)Tumor cells show genetic variability.
B)Tumor cells grow uncontrollably.
C)Tumor cells pass on mutations when they divide.
D)Tumor cells can spread throughout the body.

Question 40

Identify a difference between embryonic and adult stem cells from the following list.

A)The use of embryonic stem cells raises fewer ethical issues than the use of adult stem cells.
B)Embryonic stem cells are undifferentiated; adult stem cells are partially differentiated.
C)It is easier to obtain embryonic stem cells.
D)Adult stem cells are easier to grow in culture.

Question 41

A researcher is attempting to use RNAi to investigate the function of citrate synthase, an enzyme that is involved in the Kreb's cycle. If the researcher injected siRNAs complementary to citrate synthase mRNA into cells, what is the most likely outcome that she would observe?

A)Less citrate synthase RNA would be produced.
B)Less citrate synthase protein would be produced.
C)More citrate synthase protein would be produced.
D)More citrate synthase RNA would be produced.

Question 42

Consider the accompanying figure, which outlines cloning by nuclear transplantation. Why does the clone NOT resemble the surrogate mother?

A)The sperm came from a male donor, who would also pass some of his traits to the clone.
B)The embryonic cells are adversely influenced by the surrogate.
C)The DNA for the clone comes from the genetic donor, not the surrogate.
D)The nuclear material from the egg would influence the appearance of the clone.

Question 43

Use the accompanying figure to answer this question. The initiation of transcription requires that enhancers bind to ________.

A)DNA
B)the promoter
C)transcription factors
D)RNA polymerase

Question 44

A variety of risk factors contribute to cancers. Additionally, some cancers are more deadly than others. What can you conclude from the accompanying figure regarding cancer?

A)Pancreatic cancer resulted in more deaths in 2017 than lymphoma.
B)Alcohol only contributes to the development of liver cancer.
C)Prostate cancer only occurs in females.
D)There were over 130 million new diagnoses of colorectal cancer in 2017.

Question 45

In a typical colon cancer, the first step is ________.

A)the inactivation of a tumor-suppressor gene
B)the mutation of a tumor-suppressor gene, producing an oncogene
C)the mutation of a proto-oncogene, producing an oncogene
D)the conversion of an oncogene to a tumor-suppressor gene

Question 46

DNA microarrays can be used to determine relative levels of gene expression between samples. DNA microarrays are usually interpreted by color: green means higher mRNA levels, yellow means equal levels, and red means lower levels. If you ran the samples from the temperature experiment on a DNA microarray using the 25°C experiment as a baseline, what results do you predict you would obtain?

A)The samples from the 37°C experiment would be green and the samples from the 10°C would be red.
B)The samples from the 37°C experiment would be red and the samples from the 10°C would be green.
C)The samples from the 37°C experiment would be green and the samples from the 10°C would be yellow.
D)The samples from the 37°C experiment would be yellow and the samples from the 10°C would be red.

Question 47

What can you conclude from these results?

A)Unpacking of the hexokinase gene occurs only at 37°C.
B)Transcription of the hexokinase gene occurs less frequently at lower temperatures.
C)The levels of hexokinase protein are not affected by temperature.
D)Translation of the hexokinase gene occurs more frequently at higher temperatures.

Question 48

What can you conclude from this figure?

A)The mRNA with exon 3 is longer than the mRNA with exon 4.
B)Exon 1 contains the stop codon for the production of a protein.
C)Exon 3 and exon 4 are being alternatively spliced.
D)This process is occurring in the cytoplasm of a eukaryotic cell.

Question 49

What would be the best experiment to do next to determine if cellular hexokinase protein concentration is temperature dependent?

A)Measure the amount of hexokinase mRNA in cells at different temperatures.
B)Measure the rate of transcription of the hexokinase gene in cells at different temperatures.
C)Measure the amount of mRNA that is broken down in cells at different temperatures.
D)Measure the rate of translation of the hexokinase mRNA in cells at different temperatures.

Question 50

What can scientists achieve by injecting siRNAs into a cell via the process of RNA interference?

A)Scientists can turn genes on.
B)Scientists can prevent genes from being expressed.
C)Scientists can increase the rate of translation.

Question 51

Which is a possible result of a miRNA molecule binding to an mRNA molecule?

A)degradation of the mRNA
B)transcription of the mRNA
C)protection of the mRNA
D)addition of a cap and tail to the mRNA

Question 52

Jim came across an advertisement for an herbal supplement that claimed to cure lung cancer by targeting precancerous cells in the lungs. If this claim were true, which of the following is a possible mechanism by which it may act?

A)The supplement would increase mutation rates in proto-oncogenes.
B)The supplement would inhibit the production of tumor suppressor proteins.
C)The supplement would stimulate translation of growth factors.
D)The supplement would restrict the transcription of oncogenes.

Question 53

Jim learned that viruses can sometimes cause cancer and wants to know why. You tell him that ________.

A)a human cell can acquire a tumor-suppressor gene from a virus
B)a human cell can acquire a proto-oncogene from a virus
C)a human cell can acquire an oncogene from a virus
D)some viruses are passed from mother to child and cause "inherited" cancers

Question 54

The lac operon is shown in the accompanying figure. The lac operon is usually in the ________ position and is activated by ________.

A)on; the repressor
B)off; lactose
C)off; the repressor
D)on; the promoter

Question 55

Jim learned that some cancer cells produce more growth factors than others. Which explanation most likely explains this observation?

A)Tumor suppressor genes may have been activated in the cells with more growth factors.
B)Mutations in homeotic genes may have occurred in the cells with fewer growth factors.
C)Vitamin C and Vitamin E may have been deficient in the cells with more growth factors.
D)Proto-oncogenes may have mutated to become oncogenes in the cells with more growth factors.