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Why is it unlikely that genetically engineered strains of bacteria wouldpose a threat to the environment?
Genetically engineered strains of bacteria are poor competitors of wild strains.
-
Human genetics can be effectively studied using:
population studies of large extended families.
-
The normal human karyotype contains _______________ chromosomes.
46
-
In genomic imprinting:
the expression of a gene depends on which parent it is inherited from.
-
The Human Genome Project:
All of these.
-
The human genome contains about _______________ genes.
45,000
-
About what percentage of the human DNA codes for polypeptides?
2%
-
Polyploidy is:
the presence of multiple sets of chromosomes.
-
Aneuploidies describe:
a condition in which an extra chromosome is present or one is absent.
-
The sperm in the figure below were most likely produced by:
translocation.
-
Autosomal monosomy is not seen in live births because:
its effects are so lethal as to cause spontaneous abortion early in pregnancy.
-
Nearly half of the pregnancies that end in miscarriage have:
major chromosomal abnormalities.
-
Persons having an XO karyotype are sterile females. They have______________ syndrome.
Turner
-
Down syndrome is an example of a _____________ condition.
trisomic
-
Persons having an XXY karyotype are nearly normal males but produce few or no sperm. They have _____________ syndrome.
Klinefelter
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A karyotype reveals that an individual is XYY. Based on your knowledge of human genetics you correctly conclude that this individual is phenotypically _______ and ________.
male; fertile
-
Translocation occurs when:
part of a chromosome breaks off and attaches to a nonhomologous chromosome.
-
In a chromosomal inversion a segment of a chromosome is:
reversed.
-
Individuals who are ____________ for sickle cell hemoglobin tend to be____________ resistant to falciparum malaria, but do not experience the effects ofsickled red blood cells.
heterozygous; more
-
Gene therapy is:
replacing a mutant allele in certain body cells with a normal allele.
-
The current status of gene therapy is:
it is being evaluated to assess the risks associated with potential side effects.
-
Cells become progressively committed to specific patterns of geneactivity and developmental fate through a process known as:
determination.
-
Cells become progressively organized into recognizable structuresthrough a process known as:
morphogenesis.
-
The concept of nuclear equivalence states that:
all of the somatic cells in an adult organism have the same genes.
-
Regulation of development takes place mostly at the level of:
transcription.
-
Totipotent nuclei are capable of:
controlling the expression of other genes in the nucleus.
-
Cloning mammals has proven to be:
a process with a low success rate and a high incidence of genetic defects.
-
Cells able to divide and form some types of cells in an organism are called:
pleuripotent stem cells.
-
Totipotent human stem cells can apparently be obtained only from:
zygotes.
-
Embryonic stem cells cannot develop into ______ cells.
placental
-
The only known source of embryonic stem cells is:
early human embryos.
-
Evolution is genetic change in ____________ that occurs over time.
a population
-
Passing on traits or characteristics that were acquired during the
- lifetime of an organism to its offspring is a concept that is attributed to:
- Jean Baptiste de Lamarck.
-
On the Galapagos Islands, Charles Darwin questioned why:
the island species resembled those from South America.
-
Who proposed that the Earth’s geological features formed slowly over time, creating long periods for evolution?
Charles Lyell
-
_________________ penned an essay stating that populations have thecapability to outgrow their food supply resulting in disease, famine, and competition.
-
Evolutionary modifications that improve the survival and reproductive
- success of an organism are called:
- adaptations.
-
Differential reproductive success is equivalent to:
natural selection.
-
Darwin might have made greater advances in his theory if he had:
understood the work of Gregor Mendel.
-
During the 1920s to 1940s, biologists combined Mendelian genetics with Darwin’s theory to form a unified explanation of evolution that is referred to as:
the modern synthesis.
-
What process ultimately provides the genetic variability that naturalselection acts on during evolution?
mutation
-
Perhaps the most direct evidence for evolution comes from:
the fossil record.
-
Which of the following would be least likely to form a fossil?
an organism in the tropical rain forest
-
Fossilized remains of humans and their immediate ancestors are found:
only in relatively young rock.
-
Paleontologists have pieced together from fossils the evolution of the whale from: four-legged, land dwelling mammals.
C. sharks.
-
Bird wings and insect wings are considered to be:
homoplastic structures.
-
The front limbs of birds and bats, both wings, are considered to be:
homologous structures.
-
When populations with separate ancestors adapt in similar ways tosimilar environmental constraints, it is referred to as:
convergent evolution.
-
If two species have homologous structures:
the species are related by a common ancestry.
-
The indigenous plants and animals of the Galapagos Islands and CapeVerde Islands:
resemble the nearest mainland species, but have evolved into new species.
-
Australia has distinctive organisms, such as egg-laying mammals andpouched mammals (marsupials), because they have:
been separated and isolated from other land masses for a long period of time.
-
All of the individuals of the same species that inhabit the same place atthe same time are known as:
a population.
-
The study of the genetic variability within a population and the forcesthat change allele frequencies is:
population genetics.
-
All of the alleles for all the loci present in a population is called the:
gene pool.
-
If a population of 1000 individuals has 160 aa genotypes, assuming simple dominance by the A allele, the phenotype frequency of the dominant phenotypeis:
0.16.
-
If a population of 1000 individuals has 250 aa genotypes, assuming only 2 types of alleles (A&a), the expected a allele frequency is:
0.2.
-
A population in which the allele and genotype frequencies do not change over time is said to be in:
genetic equilibrium.
-
What is the correct equation for the Hardy-Weinberg principle?
p2 + 2pq + q2 = 1
-
In the Hardy-Weinberg equation, the term q2 refers to the frequency of:
the homozygous recessive genotype at a given locus.
-
The Hardy-Weinberg principle of genetic equilibrium tells us what toexpect when a sexually reproducing population is:
at genetic equilibrium.
-
Which of the following causes changes in allele frequencies?
All of these.
-
__________________________ is thought to be due to increased homozygosity.
Inbreeding depression
-
Positive assortative mating in a population will:
ncrease homozygosity.
-
The ultimate source of all new alleles is:
mutation.
-
Random evolutionary changes in a small breeding population is knownas:
genetic drift.
-
The process that decreases the number of organisms with phenotypesless fit to meet environmental challenges is:
natural selection.
-
In ____________ selection, individuals with a phenotype near the meanare favored over those at the phenotypic extremes.
stabilizing
-
When phenotypes are favored at one extreme of a normal distribution,____________ selection occurs.
directional
-
The presence of two or more different alleles in a population for a givenlocus is termed:
genetic polymorphism.
-
Frequency-dependent selection acts to decrease the frequency of whichphenotype in a population?
the most common phenotype
-
Mutations that may confer no apparent selective advantage in aparticular environment are referred to as:
neutral variations.
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