Random 1
DNA fingerprinting is done by applying an electric current to a gel to separate fragments of DNA within the gel.
True
DNA sequencing is done on entire chromosomes.
False
Gene therapy offers permanent relief from a variety of diseases and disorders.
False
In genetic engineering, scientists attempt to manipulate DNA in ways other than natural processes.
True
Transgenic organisms are genetically modified organisms that contain DNA from a different organism.
True
Creating recombinant DNA is one example of_______ the manipulation of DNA.
genetic engineering
Gene sequencing allows scientists to decode the ______ of an organism, its full set of genetic information.
genome
Many somatic mutations are lethal, but sometimes a mutated cell survives and grows uncontrollably, forming a(n)
tumor
An inversion is an example of a(n) ________ mutation.
chromosomal
During transcription of a chromosome, a guanine nucleotide is replaced by adenine. This substitution is an example of a(n)
point mutation.
Northern elephant seals were hunted nearly to extinction. After their numbers recovered, DNA analysis showed that northern elephant seals have much less genetic variation than southern elephant seals. This is an example of ________
the bottleneck effect (may also accept genetic drift)
Compared to larger populations, smaller populations of organisms, such as some groups of cheetahs in East Africa, accumulate mutations at a faster rate within the population. This accumulation of mutations increases the _________ of the population.
genetic load
Scientists observing a species of fish notice that some individuals exhibit a lack of dark pigment, a condition known as oligomelanism. A survey of the population years later does not find any oligomelanic fish. This loss of genetic information within the population is an example of
gene flow
In a survey of whitetail deer in an area, 2% of the deer were albinos. Ten years later, a new survey finds that 4% are albinos. This increase indicates a change in
allele frequency
In Shannon’s biology class, ten students have brown eyes, five have blue eyes, and one has green eyes. This is an example of _______ within this population of students.
variation
Prior to a muscle cell undergoing mitosis, a nucleotide in a particular gene is deleted during replication. Why is this mutation unlikely to seriously affect the organism’s offspring?
Muscle cells are somatic cells.
Assuming that a given mutation in a population is a nonlethal germ mutation, which of the following types is least likely to affect the gene pool of that population?
a nucleotide substitution
The trees in a certain area are affected by a devastating fungus. Most of the trees die, but a few survive. Seedlings from these trees reestablish the population. During a later outbreak of the same fungus, only a few of the trees die. This is an example of _________.
Genetic drift would most likely occur in which of the following populations?
A bacterium passes a plasmid to another bacterium in a process known as _________.
lateral gene transfer
List at least three factors that can affect the genetic variation within a population.
Accept any three: new combinations of alleles through reproduction, organisms dying, organisms moving out of a population, organisms moving into a population, mutations
Explain the difference between gene flow and genetic drift.
Gene flow describes the natural changes that occur within any population over time. Genetic drift describes the specific changes in allele frequency that happen within small populations that are isolated either spatially (founder effect) or by events (bottleneck effect)
What is a carcinogen?
A carcinogen is a substance that increases a person’s risk for getting cancer. Examples: tobacco smoke, radiation, certain chemicals
Why is it necessary to use restriction enzymes before sequencing a DNA molecule?
Individual DNA molecules are too long to sequence. Restriction enzymes are used to cut the DNA into smaller fragments.
Mutations to genes or chromosomes can cause all of the following except ___________.