322 Exam 3
Put the steps involved in RNA interference into the correct order.
1. Dicer cuts double-stranded RNAs. 2. Double-stranded RNAs separate. 3. Separated siRNAs bind RISC and target mRNA. 4. Target mRNA is cut.
Place the steps involved in the "BAC by BAC" approach to sequencing a genome in the correct order.
1. break individual chromosomes into smaller fragments 2. constrict contigs made of overlapping fragments 3. store contigs assembled from smaller pieces in BACs 4. sequence BACs
Place the steps involved in the "shotgun" approach to sequencing a genome in the correct order.
1. break the whole genome into fragments 2. sequence fragments with the shotgun approach 3. reconstruct scaffolds from overlapping sequences 4. assign scaffolds to known chromosomal sites
Place the steps involved in in vitro fertilization in the correct sequence.
1. oocytes are collected from an ovary 2. oocytes are transferred to a culture dish containing chemicals similar to those in the female reproductive tract 3. sperm can either be added to the culture dish or microinjected into the female cell 4. one blastocyst is transferred to the uterus
Sequencing of the first three human genomes revealed that the percent of our SNPs likely to influence our phenotypes is
<1%
Which of the following is a vector used to deliver genes in human gene therapy?
Adeno-associated virus
Which genome editing tool is most versatile and easy to use?
CRISRP-Cas9 system
A microarray is a piece of glass or plastic to which many small pieces of ______ are attached in a grid pattern.
DNA
The enzyme ___________ is used to attach DNA strands.
DNA Ligase
Select the reasons why DNA testing alone is not always sufficient for diagnosis. Choose all that apply.
Incomplete penetrance Variable expressivity Epistasis Epigenetics
What technique is utilized in most newborn screening tests?
Mass spectrometry
What information was learned from the first sequenced genomes? Check all that apply.
Numbers of copies of short sequences contribute significantly to genetic variation. Gene variants associated with certain traits were revealed in each genome. Each man had a unique collection of SNPs.
Beth and Chris know they are both carriers of the allele that causes cystic fibrosis. Which genetic test should they consider as they prepare to have children?
Preimplantation genetic diagnosis and sequencing
In _____________, a double-stranded RNA molecule separates into single strands. One of the strands prevents a complementary mRNA from being translated.
RNA interference
__________ is a gene silencing technique that is based on the fact that RNA molecules can fold into short, double-stranded regions where the base sequence is complementary.
RNA interference
Select the conditions that can be detected by standard genome sequencing. Check all that apply.
Sickle cell anemia (missense mutation in the β-globin gene) A form of cystic fibrosis caused by a nonsense mutation
You are developing cancer drugs. You wish to develop a drug that reduces expression of an oncogene. You want the mRNA encoded by the oncogene to be completely destroyed in the treated cells. Which strategy should you use?
Treatment of cancer cells with RNAi
Cancer can result from a failure of
a cell cycle checkpoint
In preimplantation genetic diagnosis, what is the source of the DNA used for genetic testing?
a cell from an embryo
An ectopic pregnancy results when
a fertilized ovum begins to develop in a blocked uterine tube.
Select the genome editing tool that is described by each sentence. a. Uses RNA b. Relies on the FokI nuclease c. Based on a bacterium that infects plants d. Can be used to remove, replace, or add more than one gene at a time e. Can be used in any species
a. CRISPR-Cas9 b. ZFN c. TALEN d. CRISPR-Cas9 e. CRISPR-Cas9
A variety of treatments are available for genetic diseases. Some treatments alter the phenotype. Others alter the underlying genotype. Determine whether each of the treatments listed alters the genotype or the phenotype. Drag each treatment to the appropriate category. a. Treatments that alter the genotype b. Treatments that alter the phenotype
a. replacement of a mutant allele through gene therapy b. removal of an affected body part, replacement of an affected body part with material from a donor, treatment of diabetes with human insulin, enzyme replacement therapy for lysosomal storage diseases, substate reduction therapy
Which of the following events at the cellular level can result in development of cancer?
activation of cancer stem cells increase in the proportion of stem cells within a tissue defective tissue repair dedifferentiation
Newborn screening using mass spectrometry identifies certain single-gene disorders by detecting
an unusual metabolite or metabolic imbalance
A variation of ________________ uses morpholinos to silence mutations that cause exons to be cut out of mRNA.
antisense technology
_____________ reproductive technologies may replace the source of a male or female gamete, aid fertilization, or provide a uterus.
assisted
The release of bacteria or plants that can detoxify pollutants is called ________
bioremediation
The use or alteration of cells or biological molecules for specific applications is called ______________.
biotechnology
Reverse transcriptase is used in the lab to make _________, which is complementary to a specific mRNA.
cDNA
When a DNA microarray experiment is conducted, the _________ are labeled with fluorescent dyes.
cDNAs from each sample
Select the genetic tests that are given prenatally. Check all that apply.
chronic villus sampling maternal serum markers sperm selection
Making many copies of a specific DNA sequence is called __________
cloning
Fluorescent DNA probes that bind to ____________ sequences on the grid are detected by a laser.
complementary
The number of copies of an individual's genome that are sequenced is termed __________
coverage
Recombinant DNA technology is used to
create many copies of a specific piece of DNA.
_________ is based on associations between chromosome structure and syndromes.
cryogenic map
As a woman ages, her fertility ____________ , and her risk of pregnancy-related problems _____________ .
decreases, increases
passenger mutation
does not cause cancer occurs in cancerous and noncancerous cells number of mutations increases with the patient's age
What are potential benefits of sequencing the genomes of newborns? Check all that apply.
earlier diagnosis of diseases Identifying conditions that may be prevented with early intervention Providing crucial information for a person's electronic health record
Tyrone has Gaucher disease. He receives recombinant glucocerebrosidase every other week in an infusion to prevent the symptoms. This treatment is an example of
enzyme replacement therapy
The portion of the genome that encodes protein is the _________
exome
Shannon and her father both have had their genomes sequenced, and they both have the same mutation in the FBN gene. This mutation causes Marfan syndrome. Shannon's father has severe heart problems in addition to other characteristics of Marfan syndrome, whereas Shannon has no heart problems, although she is tall and slender. Which phenomenon explains how Shannon and her father have the same mutation but different disease phenotypes?
expresitivity
Most cancers are the result of a single genetic change.
false
Collected oocytes and sperm are deposited in the uterine tube in ____________
gamete intrafallopian transfer.
A DNA microarray, also called a __________, is used to detect and display the mRNAs in a cell.
gene chip
Restriction enzymes are useful in creating recombinant DNA molecules because they
generate "sticky ends" by cutting at the same sequence in any DNA source.
The study of genomes is called
genomics
Cancer susceptibility is passed onto future generations when a(n) ___________ mutation has occurred.
germline
Infertility and spontaneous abortion increase with age primarily due to
higher production of oocytes with abnormal chromosome numbers.
Sequencing a human genome can now be done in ________
hours
the __________ is the complete set of human chromosomes and genes.
human genome
Current versions of the human genome have a few __________ small missing pieces.
hundred
Freezing oocytes has not been as successful as freezing sperm because
ice crystals can form in the abundant, watery cytoplasm.
Which complications of traditional gene therapy can be overcome by the CRISPR-Cas9 system? Check all that apply.
immune response to viral vectors Inserted genes disrupting off-target genes
Sperm and oocytes are mixed in a laboratory dish, along with chemicals that encourage fertilization, in ___________________.
in vitro fertilization
Identify the limitations of exome and genome sequencing. Select all correct answers.
inability to detect certain genes that reside within mitochondria DNA repeats do not show up Deletions do not show up
The inability to conceive a child after a year of frequent intercourse is _______________
infertility
In gamete intrafallopian transfer (GIFT), fertilization occurs ______
inside a woman's body
Sperm are injected directly into an oocyte in ________________
intracytoplasmic sperm injection
Donated sperm are placed into a woman's cervix or uterus in _______________.
intrauterine insemination
To create a multicellular eukaryotic transgenic organism, a researcher
introduces foreign DNA into a fertilized ovum.
Causes of female infertility
irregular menstrual cycles, high prolactin levels, reduced ovarian reserve, blockage of uterine tube, fibroid tumors in the uterine lining, pelvic inflammatory disease, endometriosis
A procedure that places an oocyte and sperm in a culture dish, allows a few cell divisions, and then places the resulting very early embryo in the oocyte donor's uterus is
ivf
a _______ is a genetic map derived from recombination data
linkage map
Oocytes may be stored by freezing them in __________
liquid nitrogen
Which of the following characteristics are typical of cancer cells?
loss of cell cycle control dedifferentiated lack contact inhibition
A ____________ is a sequence of twenty-five DNA bases attached to organic groups that are different from the usual sugar-phosphate backbone of DNA.
morpholino
To identify genes that are actively expressed, researchers isolate
mrna
Which of the following contributes to subfertility?
oligospermia
causes male infertility
oligospermia, varicose vein in scrotum, small deletion of Y chromosome, mutations androgen receptor genes, faulty apoptosis
Select the diseases or conditions that would be amenable to treatment with CRISPR-Cas9 genome editing. Choose all that apply.
phenylketonuria (missense mutations in the PAH gene) beta-thalassemia (nonsense mutation in the gene that encodes beta-globin) preventative treatment of women who have missense mutations in BRCA-1
a ___________ is constructed from overlapping DNA segments.
physical map
Small circular DNA molecules that are found in some bacteria, yeasts, and plant cells are called ________
plasmids
in __________ disease-causing genes are identified based on their location in the genome.
positional cloning
A test called _______________ can detect genetic and chromosomal abnormalities after in vitro fertilization, but before transfer of the embryo to the uterus.
preimplantation genetic diagnosis
driver mutation
provides selective growth advantage to cells known to occur in about 200 genes
A DNA molecule that includes nucleotide sequences from two different organisms is called a _________ DNA molecule.
recombinant
A(n) ___________ is a digital DNA sequence that represents the most common base at each point in a sequenced genome.
reference genome
DNA is cut into fragments by _______
restriction enzymes
A gene expression microarray has
short pieces of DNA of known sequence attached to a small plastic or glass square.
The molecules that carry out RNA interference are called ______________.
small interfering RNAs
A mutation that occurs in cells that do not develop into gametes is called a(n) ________ mutation.
somatic
Sporadic cancer is due to ________ mutations.
somatic
To test for male infertility, what can be analyzed?
sperm count, sperm motility, sperm morphology
Some restriction enzymes produce _________ that are complementary to each other.
sticky ends
Individuals and couples who can conceive a child unaided, but for whom conception may take longer than usual are _______________.
subfertile
A _________________ is a woman who carries a pregnancy for a woman who cannot become or stay pregnant.
surrogate mother
Cancer cells often have longer telomeres due to reactivation of the enzyme
telomerase
A test offered on the Web by a direct-to-consumer genetic testing company genotypes a gene for ability to taste bitter substances. This test is not regulated by the Clinical Laboratory Improvement Amendments (CLIA) because
the test provides information, not a diagnosis
Select the true statements about reference genomes. Choose all that apply.
they are haploid they are digital
An organism that contains DNA from other species is called a ____________ organism.
transgenic
A mutation present in all stages of a tumor acts early in the disease process.
true
Savior siblings born using ARTs have provided needed transplants for ailing siblings.
true
The older a tumor is, the more genetic changes it will have.
true
Whole-genome shotgunning is faster, but it misses some sections that the clone-by-clone method detects.
true
A surrogate mother donates her _________ to assist another woman who cannot become or stay pregnant.
uterus
A cloning ____________ is a DNA molecule into which another piece of DNA can be inserted.
vector
In ________________, a fertilized ovum is transferred into a woman's uterine tube.
zygote intrafallopian transfer
An IVF ovum is introduced into a woman's uterine tube in a procedure called ______________________.
zygote intrafallopian transfer.