Biology Exam Pt. 3
Select all of the following that are components of DNA. (Check all that apply.)
- A deoxyribose sugar - A phosphate group - The nitrogenous bases thymine, adenine, cytosine, and guanine
From the list provided, select all that describe the process of sickle-cell gene therapy. (Check all that apply.)
- Bone marrow removal - Ex vivo gene therapy
In genetic testing, DNA sequencing
is used to identify the incorrect nucleotide or nucleotides that caused the mutation and the disease to occur.
For the expression of a recessive trait, a person needs to inherit a
recessive allele from both of their parents.
PCR is important because it allows scientists to
All of the answer choices are correct.
Which of the following is not a reason why bacteria are used in biotechnology?
Bacteria have multiple chromosomes which allows for more DNA to be available for use in biotechnology.
What is the name of the enzyme that fits new complementary DNA nucleotides to synthesize the new daughter strand?
DNA polymerase
Which three scientists were involved in discovering DNA as genetic material?
Griffith, Hershey, and Chase
Which of the following statements best describes how a mutation changes the shape of a protein?
If a mutation occurs during DNA replication, the affected gene may produce a protein that is misfolded.
True or False: In genome editing the mutated gene is either replaced with the correct gene or completely removed.
True
Several different researchers contributed to the study of the structure of DNA. What did Rosalind Franklin contribute?
X-ray crystallography was used to show DNA is a repeating helical structure
The role of vectors in gene therapy is to
deliver the genetic material to the cells of interest.
True or False: To transcribe something is to make an identical copy, i.e., if the original is DNA, the transcribed copy is also DNA.
false
PCR is a technique used in the laboratory to ___.
make millions of copies of a gene of interest.
From the list provided, select all techniques that are used to analyze DNA for mutations. (Check all that apply.)
- PCR - Gene cloning - Karotypes - Microarray
For the following pedigree showing the inheritance of a recessive genetic disease, what does the green circle in the fourth generation represent?
A female with the disease
Genes can be inserted into plasmid DNA and cloned into bacteria. This will produce bacteria that have recombinant DNA and will
All of the answer choices are correct.
Which researcher used X-ray crystallography to suggest that DNA is a double helix and was highly repetitive?
Franklin
Red blood cells are responsible for __________.
Gas exchange throughout the body
During gene therapy, bone marrow stem cells are removed from the individual. What must happen to those cells before they are injected back into the individual?
Viruses act as vectors to carry the normal gene into the genome of the stem cells.
The susceptibility for a certain disease may be determined with a genetic marker test. This technique looks for
a different banding pattern of DNA that has been cut with restriction enzymes to observe changes.
The nucleotides along one side of a DNA molecule are connected to each other by __________ between phosphate groups and sugar molecules.
covalent bonds
DNA strands are complementary of each other. This means if one strand has an adenine the other has a __________, and if one strand has a guanine the other has a/an __________.
thymine; cytosine
What type of cells are used to collect DNA for genetic testing?
white blood cells
Sickle-cell disease is a disorder that results in malformed hemoglobin molecules. What is the result of this in terms of hemoglobin function?
Hemoglobin has a reduced ability to bind to and transport oxygen in red blood cells.
Which of the following is the overall goal of PCR?
To create several copies of a segment of DNA in a tube
The overall goal of gene expression is to make
a structural protein that can be used by the cell.
Which of the following is not required for gene cloning by bacteria?
gel electrophoresis
Crossing-over produces genetic variation during prophase I of meiosis I. This occurs when
homologous chromosomes come close together and a rearrangement of alleles occurs.
In gene expression, the goal of translation is to
read codons and incorporate corresponding amino acids into a growing polypeptide chain.
Sickle-cell disease results in malformed hemoglobin molecules. Which cell type contains millions of hemoglobin molecules per cell?
red blood cells
In humans, male gametes are called ______, while female gametes are called ______.
sperm; eggs
During elongation in transcription, RNA polymerase creates a complementary mRNA sequence from a gene. Provide the mRNA sequence from the given gene sequence. TACGGCACCCAGCATT
AUGCCGUGGGUCGUAA
The information contained in genes is expressed
All of these are required for gene expression to be complete.
Based on the structure and arrangements of nucleotides in the __________ molecule, the molecule is an information molecule. It stores instructions and is read to produce proteins that direct cellular reproduction, produce new cellular components, and initiate cellular reproduction.
DNA
Which of the following is the main difference between in vivo and ex vivo gene therapy?
Ex vivo gene therapy occurs outside the body and in vivo gene therapy occurs inside the body.
Which of the following traits are considered to be inheritable?
Eye color
Mendel crossed pea plants dominant for two different traits (tall and green pods) with pea plants recessive for those same two traits (short and yellow pods). This cross resulted in pea plants that had combinations of all four traits (tall with green pods, tall with yellow pods, short with green pods, and short with yellow pods). Which law of inheritance best describes why this happens?
The law of independent assortment
Which of the following best explains the role of transcription in a cell?
To produce a mRNA molecule to deliver the genetic instructions outside the nucleus.
In the human life cycle, gametes are formed through the process of ______, and all other cells are formed through the process of ______.
meiosis; mitosis
Sickle-cell disease is a recessive genetic disease. This means
two copies of the recessive allele must be present in order for the disease to be expressed.
Which of the following statements concerning gene is/are true? Select all that apply.
- A gene is a segment of DNA that determines a certain trait. - An allele is a variation of a given gene - Allele variations are due to small changes in the nucleotide sequence within the gene that sometimes change the structure of a protein and ultimately its function.
Law of segregation
- Each individual has two factors for each trait and these factors (alleles) separate during the formation of the gamete - Each individual is diploid or has two factors for each trait, but it produces gametes that have only one factor for each trait - Fertilization produces a new individual with two factors for each trait
Law of independent assortment
- Genes for different traits assort independently of one another in the formation of gametes - As long as traits are on separate chromosomes, all possible combinations of factors can occur in the gametes
Two parents with Type A and Type B blood have a child with Type AB blood. How is this possible?
Type A blood is codominant with Type B blood, so both alleles are expressed equally.
CRISPR may work to treat sickle-cell disease by targeting
faulty portions of the hemoglobin gene within the genome of cells and removing and replacing those portions with normal sequences of nucleotides.
Meiosis is different from mitosis in that meiosis results in
four haploid daughter cells that are genetically diverse, whereas mitosis results in two diploid daughter cells that are genetically identical.
Mendel's experiments led him to the conclusion that individuals have two factors for each trait, which that separate during gamete formation, resulting in gametes with one factor for each trait. In addition, fertilization results in a new individual with two factors for each trait again. He referred to this as the __________.
law of segregation
Which of the following statements best describes the human life cycle?
Adult humans produce haploid sex cells through meiosis. During fertilization, these cells form a diploid zygote. The zygote divides through mitosis to form a human.
DNA replication is considered to be ______ because the end product consists of one old strand and one newly synthesized strand.
semiconservative
During translation, a polypeptide chain is created using an RNA template. Which of the following components is responsible for bringing amino acids to the growing polypeptide chain?
tRNA
