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WorksheetsRevision chapter 7 & 8
Total questions: 24
Worksheet time: 48mins
Which of the following would most likely cause a mutation with the greatest deleterious effect?
An insertion of a nucleotide triplet into a DNA strand that codes for an mRNA
A single addition of a nucleotide in a DNA strand that codes for an mRNA
A deletion of a nucleotide triplet from a DNA strand that codes for an mRNA
All of these
Helen has type I osteogenesis imperfecta (OI), a genetic skeletal disorder. Shown below is her DNA sequence for a portion of the coding region:
Helen 5'-AAACTCCACTTCTTCCAGTAC-3'
Normal 5'-AAACTCACTTCTTCCAGTAC-3'
What type of mutation does Helen carry?
Missense
Nonsense
Deletion
Frameshift
Suppose a research study shows that people who suffer from severe depression has mutation in the hypothetical DEP gene.
DEP gene for individuals without depression:
5'-ATG ACG TTT GAA ATT CAG TCT AGA-3'
DEP gene for affected individuals:
5'-ATG ACG TTT GAA ATT TAG TCT AGA-3'
The mutation identified is most likely a
missense
nonsense
frameshift
deletion
Sickle cell anemia is a disease caused by the substitution of an incorrect nucleotide into the DNA sequence for a particular gene. The amino acids are still added to the growing protein chain, but the symptoms of sickle cell anemia result. This is an example of a
frameshift mutation.
missense mutation.
nonsense mutation.
thymine dimer mutation.
Which of the following DNA strands would serve as a template for the amino acid sequence shown in the diagram?
3′-ATGCGACCAGCACGT-5′
3′-AUGCCACUAGCACGU-5′
3′-TACGGTGATCGTGCA-5′
3′-UACGGUGAUCGUGCA-5′
Which of the following best explains how mutations in DNA can result in the expression of a new phenotype?
A different polypeptide is produced.
The polarity of tRNA becomes the opposite of that of DNA.
Nucleic acids are methylated.
The gene is now read in the 3' to 5' direction.
What condition is shown in the human karyotype seen above?
Aneuploid
Polyploid
Diploid
Haploid
Polyploidy is lethal in human beings, however for some organisms it can results in larger organisms. Which organisms may flourish under polyploidy conditions?
protists
bacteria
prokaryotic cells
plants
Which of these mutations in a gene will MOST LIKELY result in a shortened protein with a long sequence of substituted amino acids?
Missense substitution of one nucleotide
Insertion of two nucleotides
Deletion of three nucleotides
Nonsense substitution of five nucleotides
Triticale is a hybrid of wheat (Triticum turgidum) and rye (Secale cereale), bred to demonstrate the most desirable characteristics of both species. The resulting hybrid possesses four chromosome sets from the maternal wheat plant and two sets from the paternal rye plant. What is the ploidy of these hybrids?
Diploid (2n)
Triploid (3n)
Tetraploid (4n)
Hexaploid (6n)
Edward's syndrome is the result of an additional 18th chromosome present in a fertilized embryo. Which of the following events could lead to the presence of this additional chromosome in a zygote?
Crossing over in meiosis I
Nondisjunction in meiosis II
A deletion during meiosis II
A deletion during meiosis I
A horse has 64 chromosomes, while a zebra has 46. In rare cases, it is possible to cause these two species to hybridize, creating offspring that are
fertile, with 55 chromosomes
sterile, with 46 chromosomes
sterile, with 55 chromosomes
sterile, with 64 chromosomes
Which of the following is the most important discovery that leads to the development of rDNA (recombinant DNA) technology
discovery of double helix model by Watson and crick
discovery of DNA as genetic material
discovery of restriction enzymes
all of these
In order to insert a foreign gene into a plasmid, both must
have identical DNA sequences
originate from the same type of cell
be cut by the same restriction enzyme
be of the same length
Certain restriction enzymes produce cohesive (sticky) ends. This means that they:
cut both DNA strands at the same base pair.
cut in regions of high GC content, leaving ends that can form more hydrogen bonds than ends of high AT content.
make a staggered double-strand cut, leaving ends with a few nucleotides of single-stranded DNA protruding.
make ends that can anneal to cohesive ends generated by any other restriction enzyme.E)
In the laboratory, recombinant plasmids are commonly introduced into bacterial cells by:
electrophoresis – a gentle low-voltage gradient draws the DNA into the cell.
infection with a bacteriophage that carries the plasmid.
transformation – heat shock of the cells incubated with plasmid DNA in the presence of CaCl2.
mixing plasmids with an extract of broken cells.
The biological role of restriction enzymes is to:
aid recombinant DNA research.
degrade foreign DNA that enters a bacterium.
make bacteria resistant to antibiotics.
restrict the damage to DNA by ultraviolet light.
The E. coli recombinant plasmid pBR322 has been widely utilized in genetic engineering experiments. pBR322 has all of the following features except :
a number of conveniently located recognition sites for restriction enzymes.
a number of palindromic sequences near the EcoRI site, which permit the plasmid to assume a conformation that protects newly inserted DNA from nuclease degradation.
a replication origin, which permits it to replicate autonomously.
resistance to two different antibiotics, which permits rapid screening for recombinant plasmids containing foreign DNA.
The mechanism of intake of DNA fragments from the surrounding medium by a cell is called
transformation
transduction
conjugation
amplification
An animal, that has gained new genetic information from the acquisition of foreign DNA, is considered as
a chimera
a transgenic animal
a vector
an enzyme that links DNA molecules
Which of the following vector can maintain the largest fragment of foreign DNA?
YAC
Cosmid
Plasmid
Phage
The deliberate modifications of an organism’s genetic information by directly changing its nucleic acid content is a subject matter of
genetic engineering
population genetics
microbiology
protein engineering
Which of the following is obtained using processed mRNA molecules as a template?
rDNA
mDNA
cDNA
tDNA
Problems in obtaining large amounts of proteins encoded by recombinant genes can often be overcome by using
BACS
expression vectors
YACS
all of these
