Biology Exam 2
You are investigating a rare genetic brain disorder and would like to identify the gene responsible, clone it, and determine its function. A very small protein isolated from the brains of healthy individuals is not present in brain cells of individuals who have the disease. The protein has a molecular weight of about 1,000 Da. If the molecular weight of a typical amino acid is 100 Da, you expect the protein to be _____ amino acids long. The corresponding mRNA coding sequence would have ______ ribonucleotides (do not include the stop codon)
10, 30
Fill in the blank: If a segment of double-stranded DNA contains 20% guanine, it will contain ______% adenine.
30
Fill in the Blanks (one letter per blank): If you transcribe the template strand shown below, the mRNA sequence would be... Template Strand: 3' CTACGCGATCCG 5'
5' GAU-GCG-CUA-GGC 3'
At what stage is a single cell removed for preimplantation genetic screening?
8-cell or 16-cell
Which of the following mutations is MOST likely to severely affect the protein coded for by a gene?
A frameshift mutation at the beginning of the gene
The ends of the DNA molecule shown in the image below are labeled as A, B, C, and D. Select ALL of the ends that would be considered 5' ends. (normal DNA strand)
D and A
Catalyzes the joining of Okazaki fragments
DNA ligase
Removes the RNA primer and replaces it with DNA
DNA polymerase I
Synthesizes the daughter strands
DNA polymerase III
Which of the following does NOT contain a fertility factor?
F-
Fill in the blank: If one strand of a DNA molecule is 5' CATCGA 3' , then the complementary strand would be 3' ____________ 5'
GTAGCT
When does independent assortment occur?
Metaphase I of meiosis
What are prions?
Misfolded versions of normal protein that can cause disease
Which of the following types of genetic testing are required by the state of Tennessee?
Newborn genetic screening
Which of the following is TRUE about protein folding?
Some proteins can fold spontaneously.
Fill in the blank: If one strand of a DNA molecule is 3' ACTGAAGTCG 5' , then the complementary strand would be 5' ____________ 3'
TGACTTCAGC
Top Strand: 3' CTACGCGATCCG 5' Bottom Strand: 5' GATGCGCTAGGC 3' Which is the template stand?
Top
Can two genes be located on the same chromosome and be considered unlinked?
Yes
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: strand slippage
addition/deletion of trinucleotide repeats
Label each of the following as being a component of a nucleotide or an amino acid: Amino group
amino acid
Label each of the following as being a component of a nucleotide or an amino acid: Carboxyl group
amino acid
Label each of the following as being a component of a nucleotide or an amino acid: Side chain (R group)
amino acid
What is exposed on each end of a protein? N-terminus
amino acid
protein monomer
amino acid
A needle is used to penetrate the uterus and placenta to withdraw amniotic fluid.
amniocentesis
Label each description with the correct DNA repair mechanism: Repairs a damaged DNA base: Repairs a damaged DNA base
base excision repair
Label each spontaneous mutation or mutagen as causing a base-substitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: DNA polymerase adds a non-complementary base during DNA replication
base-substitution
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: Deaminating agents
base-substitution
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: Deamination
base-substitution
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: Depurination
base-substitution
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: Hydroxylating agents
base-substitution
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: Nucleotide base analogs
base-substitution
Top Strand: 3' CTACGCGATCCG 5' Bottom Strand: 5' GATGCGCTAGGC 3' Which is the coding strand?
bottom
Top Strand: 3' CTACGCGATCCG 5' Bottom Strand: 5' GATGCGCTAGGC 3' Which is the non-template strand?
bottom
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: Alkylating agents
breaks in DNA
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: Oxidizing agents
breaks in DNA
What is exposed on each end of a protein? C-terminus
carboxyl group
A couple is trying to decide whether to have children of their own or to adopt. They want to know the probability of them having a child with Sickle Cell Disease.
carrier genetic screening
A small tube is used to suction off cells from the outside of the placenta.
chorionic villus sampling
Once the ribosome locks onto the first codon, the reading frame is established.
code is non-overlapping
Ben was adopted, so he is curious about his ancestry.
direct-to-consumer genetic testing
TRUE or FALSE: The leading strand is synthesized in the 5' --> 3' direction, and the lagging strand is synthesized in the 3' --> 5' direction
false
Fetal cells are collected from a sample of the mother's blood.
fetal cell sorting
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: Intercalating agents
frameshift
Label each spontaneous mutation or mutagen as causing a base-subtitution, addition/deletion of trinucleotide repeats, frameshift, or breaks in DNA: UV radiation
frameshift
The addition or deletion of one or a few base pairs that shifts the reading frame of the mRNA.
frameshift mutation
Catalyzes the breaking of hydrogen bonds between base pairs
helicase
__________ gene transfer is the non-reproductive transfer of DNA from one organism to another
horizontal
What is exposed on each end of a nucleic acid? 3' end
hydroxyl group
Label each description with the correct DNA repair mechanism: Repairs a damaged DNA base: A base pair mismatch is repaired by recognizing which is the newly synthesized DNA strand
mismatch repair
A point mutation that changes one amino acid for another within a protein.
missense mutation
A nurse just collected blood for the RUSP.
newborn geneticscreening
Label each description with the correct DNA repair mechanism: Repairs a damaged DNA base: Repairs double-strand breaks during G1
nonhomologous end joining
A point mutation that converts an amino-acid-specifying codon into a stop codon.
nonsense mutation
Label each of the following as being a component of a nucleotide or an amino acid: 5-carbon sugar
nucleotide
Label each of the following as being a component of a nucleotide or an amino acid: Nitrogenous base
nucleotide
Label each of the following as being a component of a nucleotide or an amino acid: Phosphate group
nucleotide
Nucleic acid monomer
nucleotide
Label each description with the correct DNA repair mechanism: Repairs a damaged DNA base: The mechanism that repairs thymine dimers in humans
nucleotide excision repair
protein bonds
peptide
What is exposed on each end of a nucleic acid? 5' end
phosphate group
Nucleic acid bonds
phosphodiester
Label each description with the correct DNA repair mechanism: Repairs a damaged DNA base: A mechanism that uses visible light to break the covalent bonds in a thymine dimer
photoreactive repair
A couple is undergoing in vitro fertilization. They want to make sure that they have the best chances of having a successful pregnancy.
preimplantation genetic screening
A couple's first child has cystic fibrosis. They are pregnant with their second child and want to know if the fetus has the same disease.
prenatal genetic testing
Caroline is 21 years old and her mother was just diagnosed with Huntington's Disease. She wants to know if she will develop the disease later in life.
presymptomatic genetic testing
This level is the sequence of amino acids in a protein.
primary
Catalyzes the synthesis of the RNA primer
primase
Label each description with the correct DNA repair mechanism: Repairs a damaged DNA base: DNA polymerase III recognizes it added the wrong base, removes it, and then continues replicating the DNA
proofreading
Label each base as a purine or pyrimidine: Adenine
purine
Label each base as a purine or pyrimidine: Guanine
purine
Label each base as a purine or pyrimidine: Cytosine
pyrimidine
Label each base as a purine or pyrimidine: Thymine
pyrimidine
Label each base as a purine or pyrimidine: Uracil
pyrimidine
This level is the result of two or more protein subunits assembling to form a larger, biologically active protein complex.
quaternary
This level describes the alpha-helices and beta-sheets that are formed by hydrogen bonding between the backbone atoms located near each other in the polypeptide chain.
secondary
DNA undergoes _______.
semiconservative replication
A point mutation that changes the sequence of codon without changing the amino acid that is specified.
silent mutation
Stabilizes the single-stranded DNA
single-stranded DNA-binding
Label each description with the correct DNA repair mechanism: Repairs a damaged DNA base: Repairs double-strand breaks after DNA replication has occurred
synthesis-dependent strand annealing
This level is achieved when a protein folds into a compact, three-dimensional shape stabilized by interactions between side-chain R groups of amino acids.
tertiary
With a few minor exceptions, all codons specify the same amino acids in all organisms.
the code is nearly universal
Most amino acids are coded for by more than one codon.
the code is redundant
A given codon never codes for more than one amino acid.
the code is unambiguous
Which of the following is NOT a nitrogenous base found in RNA?
thymine
Top Strand: 3' CTACGCGATCCG 5' Bottom Strand: 5' GATGCGCTAGGC 3' Which is the non-coding strand?
top
Breaks and rejoins the DNA double helix to relieve tension
topoisomerase
Fill in the blanks for the central dogma of biology. DNA >> _________>> mRNA >>_________>>>protein
transcription, translation
Which type of genetic recombination in bacteria utilizes bacteriophages?
transduction
Bacterial cells have to be competent to take up DNA during _________
transformation
BRCA1 and BRCA2 are ______
tumor-suppressor genes
_________ gene transfer is the transfer of DNA from parent to offspring
vertical
