Term
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Definition
| a sequence of nucleotides that is complementary to the nucleotide sequence in a gene under study; used to locate a given gene within a DNA library. |
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Term
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Definition
| A technique in which molecules (such as DNA fragments) are placed on restricted tracks in a thin sheet of gelatinous material and exposed to an electric field; the molecules then migrate at a rate determined by certain characteristics, such as length. |
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Term
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Definition
| modification of genetic material to achieve specific goals |
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Term
| Genetically modified organisms |
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Definition
Organisms that have been produced through the techniques of genetic engineering. |
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Term
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Definition
a small circular piece of DNA located in the cytoplasm of many bacteria; normally does not carry genes required for normal functioning of the bacterium but may carry genes that assist bacterial survival in certain environments, such as a gene for antibiotic resistance. |
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Term
| Polymerase chain reaction (PCR): |
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Definition
| A method of producing virtually unlimited numbers of copies of a specific piece of DNA, starting with as little as one copy of the desired DNA |
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Term
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Definition
DNA that has been altered by the recombination of genes from different organism, typically from a different species. |
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Term
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Definition
an enzyme. Normally isolated from bacteria, that cuts double-stranded DNA at a specific nucleotide sequence; the nucleotide sequence that is cut differs for different restriction enzymes. |
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Term
| Restriction Fragment length polymorphism (RFLP) |
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Definition
a difference in the length of restriction fragments, produced by cutting samples of DNA from different individuals of the same species with the same set of restriction enzymes; the result of differences in nucleotide sequences among individuals of the same species. |
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Term
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Definition
an undifferentiated cell that is capable of dividing and giving rise to one or more distinct types of differentiated cells. |
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Term
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Definition
a method of acquiring new genes, whereby DNA from one bacterium (normally released after the death if the bacterium) becomes incorporated into the DNA of another, living bacterium. |
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Term
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Definition
| to an animal or plant the expresses DNA derived from another species. |
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Term
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Definition
The procedure for sampling the amniotic fluid surrounding a fetus: A sterile needle is inserted through the abdominal wall, uterus, and amniotic sac of pregnant woman; 10 to 20 millimeters of amniotic fluid are withdrawn. Various tests may be performed on the fluid and the fetal cells suspended in it to provide information on the developmental and genetic state of fetus. |
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Term
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Definition
An industrial or commercial use or alteration of organisms, cells, or biological molecules to achieve specific practical goals. |
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Term
| Chorionic Villus Sampling (CVS): |
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Definition
A procedure for sampling cells from the chorionic villi produced by a fetus: A tube is inserted into the uterus of a pregnant woman, and a small sample of villi are suctioned off for genetic and biochemical analyses. |
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Term
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Definition
The use of restriction enzymes to cut DNA segments into a unique set of restriction fragments from one individual that can be distinguished from the restriction fragments of other individuals by gel electrophoresis. |
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Term
Transformation is the process by which foreign ______ is taken up from a cell’s environment, permanently changing the characteristics of a cell and its offspring.
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Definition
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Term
Antibiotic resistance can be passed among bacterial strains by _____________.
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Definition
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Term
| Analysis of restriction fragment length polymorphisms (RFLPs) is a rapid way to examine differences in the _____________. |
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Definition
| DNA sequences of individuals |
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Term
| A pair of prospective parents is concerned about the risk of having a child with cystic fibrosis, because both the man and woman have a sibling who died from the disease. They undergo genetic testing and find that each carries one cystic fibrosis allele and one normal allele. What is the likelihood that their unborn child will have cystic fibrosis? (Recall that cystic fibrosis results from a recessive mutation.) |
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Definition
| 25% (The chance that this baby will have cystic fibrosis is 1 in 4.) |
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Term
| Imagine you are looking at a DNA fingerprint that shows an STR pattern of a mother's DNA and her child's DNA. Will all of the bands on the Southern Blot showing the child's DNA match those of the mother? |
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Definition
| No, because the father contributed half of the child's DNA |
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Term
| What are restriction enzymes? |
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Definition
| enzymes that cleave through a DNA helix wherever they encounter a specific sequence of nucleotides |
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Term
What is a restriction fragment length polymorphism?
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Definition
| different sizes of restriction fragments from two DNA molecules that are produced by a restriction enzyme |
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Term
| __________ is any commercial use or alteration of organisms, cells, or molecules to achieve specific goals. |
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Definition
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Term
Bacteria can pick up and utilize __________, which can change physical traits of bacteria.
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Definition
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Term
Gel __________ uses physical properties of DNA fragments to help separate restriction fragments according to size.
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Definition
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Term
An artificial gene reproduction technique that helps to produce human insulin is called the __________ chain reaction (PCR).
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Definition
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Term
The modification of genetic material to achieve specific goals is called __________.
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Definition
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Term
| To clone a gene, you first isolate the gene of interest and then you insert it into a __________, which then can be replicated inside bacteria. |
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Definition
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Term
Because potatoes engineered to produce vaccines must be eaten raw, researchers are now working to produce vaccine-containing __________.
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Definition
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Term
| Making transgenic animals usually involves injecting the desired DNA into a(n) __________. |
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Definition
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Term
| In the first step of the polymerase chain reaction (PCR), __________ is used to separate the double helix of DNA into single strands. |
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Definition
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Term
| Gel electrophoresis is used to __________. |
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Definition
| separate DNA fragments by size |
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Term
Researchers must design short pieces of DNA that are complementary to DNA on either side of the segment to be amplified. These small pieces are called __________.
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Definition
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Term
STR polymorphisms can be used to identify individuals because __________.
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Definition
| individuals are genetically unique |
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Term
| The primary goal of human gene therapy is __________. |
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Definition
| to correct genetic disorders by inserting normal genes in place of defective ones |
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Term
| The polymerase chain reaction |
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Definition
can produce billions of copies of a DNA fragment in several hours |
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Term
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Definition
| have been genetically engineered to lack a specific mouse gene |
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Term
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Definition
| can involve analysis of RFLPs |
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Term
A child with a single allele for sickle-cell anemia
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Definition
will be able to lead a perfectly normal life |
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Term
| Which of the following describes an example of DNA recombination? |
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Definition
| Any organism that utilizes sexual reproduction and a virul infection resulting in a common cold. |
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Term
| What is the "polymerase chain reaction" (PCR) technique? |
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Definition
| | A technique that has led to the development of genetic screening tests of newborns for genetic disease once the nucleotide sequence of the disease causing gene is known a technique that allows investigators to determine the nucleotide sequence of a given gene | | an elegant chemical technique that utilizes the natural ability of DNA polymerase to synthesize DNA that is complementary to the parent DNA fragments | | a technique that incorporates repeated cycles of heating and cooling of DNA segments in the presence of primers and heat-resistant DNA polymerase |
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Term
| What benefit does administration of genetically engineered human insulin provide to patients that pig/bovine insulin does not? |
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Definition
Allergic reactions were avoided by using the recombinant human insulin. It could be produced in large quantities using bacteria/yeast genetically engineered to carry the human insulin gene. |
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Term
| What are some of the problems associated with the use of genetic screens for cystic fibrosis? |
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Definition
Ethical dilemmas: Individual carriers of the CF allele (Should they even attempt to conceive?), societal and insurance carriers (Should they be forced to bear the financial costs?). potential genetic discrimination by insurance companies |
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Term
| Which of the following sources of DNA could be used in DNA forensic analysis? |
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Definition
| all of them: hair folicle, saliva, semen and blood. |
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Term
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Definition
| isolated from bacterial cells, used to produce DNA fingerprints, used to creat recombinant plasmids and used to create a DNA library. |
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Term
| Restriction fragment length polymorphisms |
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Definition
| can be used to detect differences in DNA among individuals, have been used to identify human genes, can be used to analyze fetal cells to detect disorders prenatally, and are produced through the use of restriction enzymes |
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Term
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Definition
| a trait that increases the ability of an individual to survive and reproduce campared to individuals without trait. |
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Term
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Definition
| The rise of many new species in a relatively short time as a result of a sinlge species that incades different habitats and evolves under different environmental pressures in those habitats. |
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Term
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Definition
| for any given gene, the relative proportion of each allele of that gene in a population. |
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Term
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Definition
speciation that occurs when two populations are seperated by a physical barrier that prevents gene flow between them(geographical isolation) |
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Term
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Definition
| A type of behavior that may decrease the reproductive success of the individual performingnit but benefits that of other individuals |
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Term
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Definition
Structures that have similar functions and superficially similar appearance but very differend anatomies, such as the wings of insects and birds. The similarities are due to similar environmental pressures rather than to common ancestry |
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Term
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Definition
| A selective breeding procedure in which only those individuals with particular traits are chosen as breeders; mainly to enhance desirable traits in domestic plants and aminals; may also be used in evolutionary biology experiments. |
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Term
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Definition
| The hyposthesis that EArth has experienced a series of geological catastrophes, probably imposed by a supernatural being, that accounts for the multitude of species both extinct and modern, and preserves creationism. |
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Term
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Definition
| The evolution of adaptations in two species due to their extensive interactions with one another, such that each species acts as a major force of natural seletion on the other |
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Term
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Definition
interaction among individuals who attempt to utilize a resource(for example, food or space) that is limited relative to the demand for it. |
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Term
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Definition
| The independent evolution of similar structures among unrelated organisms as a result of similar environmental pressures |
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Term
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Definition
| A type of natural selection in which one extreme phenotype is favored over all others. |
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Term
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Definition
| a type of natural selection in which both extreme phenotypes are favored over the average phenotype. |
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Term
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Definition
| a population in which the allele frequencies and the distribution of genotypes do not change from generation to generation. |
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Term
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Definition
| the descent of modern organisms with modification from preexisting life-forms; strictly speaking and change in the proportions of different genotypes in a population from one generation to the next. |
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Term
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Definition
| The death of all members of a species. |
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Term
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Definition
| The reproductive success of an organism, usually expressed in relation to the average reproductive success of all individuals in the same population. |
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Term
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Definition
| The remains of a dead organism, normally preserved in a rock; maybe petrified bones or wood; shells; impressions of body forms such asfeathers, skin or leaves; or markings made by organisms, such as footprints. |
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Term
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Definition
| A type of genetic drift in which an isolatied population founded bt a small number of individuals may develop allele frequencies that are very different from those of the parent populationas a result of chance inclustion of disproportionate numbers of certain alleles in the founders. |
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Term
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Definition
| The movement of alleles from one populations to another owing to the migration of individual organisms |
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Term
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Definition
| the total of all alleles of all genes in a population; for a single gene, the total of all the alleles for that gene that occur in a population. |
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Term
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Definition
| A change in the allele frequencies of a small population purely by chance. |
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Term
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Definition
A mathmatical model proposing that, under certain conditions, the allele frequencies and genotype frquencies in a sexually reproducing population will remain constant over generations. |
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Term
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Definition
| structures that may differ in function but that have similar anatomy, presumable because the organsims that possess them have descended from common ancestors. |
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Term
| Inheritance of acquired characteristics |
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Definition
| The hypothesis that organisms' bodies change during their lifetimes by use and disuse and that these changes are inherited by their offspring. |
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Term
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Definition
| a morphological, physiological, behavioral, or ecological difference that prevents members of two species from interbreeding. |
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Term
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Definition
| A type of natural selection that favors a certain allele because it increases the survival or reproductive success of relatives that bear the same allele. |
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Term
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Definition
| A change in the base sequence of DNA in a dene; normailly refers to a genetic change in significant enough to alter the appearance or function of the organism |
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Term
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Definition
The unequal survival and reproduction of organisms due to environmental forces, resultingg in the presercation of favorable adaptations. Usually, natural selection refers specifically to differential survival and reproduction on the basis of genetic differences among individuals |
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Term
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Definition
| Having more than two homologous chromosomes of each type. |
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Term
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Definition
| all members of a particular species within an ecosystem, found in the same time and place and actually or potentially interbreeding. |
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Term
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Definition
| a form of genetic drift in which a population becomes extrememely small; may lead to differences in allel frequencies as compared with other populations of the species and to a loss in genetic variability. |
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Term
| Postmating isolating mechanism |
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Definition
| any structure, physiological function, or developmental abnomality that prevents organisms of two differenct populations, once mating has occured, from producing vigorous, fertile offspring. |
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Term
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Definition
| The act of killing an eating another living organism |
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Term
| Premating Isolating Mechanism |
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Definition
| and structural, physiological function, or behavior that prevents organisms of two different populations from exchanging gametes. |
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Term
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Definition
the failure of organisms of one population to breed successfully with members of another; may be due to prematingor postmating isolating mechanisms |
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Term
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Definition
| A type of natural selection in which the choice of mates by one sex is the selective agent. |
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Term
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Definition
The process of species formation, in which a single species splits into two or more species. |
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Term
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Definition
| The basic unit of taxonomy classification, consisting of populations of closely related and similar organisms. In sexually, reproducing organisms, a species can be defined as a population, or series of populations of organisms that interbreed freely with one another under natural conditions but that do not interbreed with members of other species. |
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Term
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Definition
| A type of natural selection in which those organisms that display extreme phenotypes are sekected against. |
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Term
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Definition
| Speciation that occurs in populations that are not physically divided; normally due to ecological isolation or chromosomal aberrations (such as polyploidy) |
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Term
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Definition
| The hypothesis that Earth developed gradually through natural processes, similar to those at work today, that occur over long periods of time. |
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Term
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Definition
| A structure that serves not apparent purpose but is homologous to functional structures in related organisms and provides evidence of evolution. |
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Term
| The ability of organisms to pass on to their offspring physical changes that the parents developed during their own lifetimes is known as _______. |
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Definition
| inheritance of acquired characteristics |
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Term
| Structures that may differ in function but that have similar anatomy, presumably because of descent from common ancestors, are called ______. |
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Definition
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Term
Structures that serve no apparent purpose but are homologous to functional structures in related organisms are called _______.
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Definition
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Term
Structures that have similar functions and superficially similar appearance but very different anatomy, such as the wings of insects and birds, are called _________. The similarities are due to similar environmental pressures rather than to common ancestry.
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Definition
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Term
The ostrich is a large, flightless bird. Its wings, therefore, represent _______.
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Definition
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Term
Which of the following lines of evidence support(s) the idea that evolution occurs?
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Definition
the fossil record artificial selection comparative anatomy and embryology genetic and biochemical analyses |
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Term
| All vertebrate embryos resemble each other during the early stages of development. For example, fish, turtles, chickens, mice, and humans develop tails and gill slits during early stages of development. This suggests that _________. |
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Definition
ancestral vertebrates possessed genes that directed the development of tails and gill slits, and all of their descendants still retain those genes early embryonic development is conservative genes that modify the developmental pathways in vertebrates arose later in evolution |
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Term
| Which of the following is NOT one of the main points of Darwin’s theory of evolution? |
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Definition
| Evolution is gradual and continuous. | | | Species are formed and adapt by the process of natural selection. | | | Contemporary species share a common descent. | | | Life on Earth is quite old. |
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Term
| Which of the following is a basic requirement for natural selection to be an effective evolutionary force? |
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Definition
| A population exhibits some genetic variability. |
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Term
What does the idea of "uniformitarianism" suggest about the geological record and the age of Earth?
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Definition
| Natural processes (e.g., sedimentation due to river flow) occurring over long stretches of time accounted for the thick layers of rock where fossils are found, rather than cataclysmic events |
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Term
| What was the untested weakness in Darwin's manifest On the Origin of Species? |
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Definition
| the passage of traits from generation to generation, and that variations in these traits occurred randomly |
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Term
| Which of the following would be considered to be an example of analogous structures? |
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Definition
| superficially similar structures in unrelated species |
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Term
Which of the following would describe artificial selection?
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Definition
| breeding organisms for the purpose of generating certain features or traits (e.g., dog breeds) |
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Term
| Which of the following people allowed for species to change over time? |
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Definition
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Term
Charles Darwin was NOT influenced by which of the following people in formulating his ideas about natural selection?
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Definition
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Term
| Which of the following is an incorrect statement about mutation? |
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Definition
| Mutations that are favored by selection are more likely to occur. |
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Term
You are a biologist studying a natural population of mice, and you observe that in one area the proportion of darker colored mice is greater than the proportion of lighter colored mice. In another area, the opposite is true. You find that only the area with more dark mice has predators. Therefore, you hypothesize that darker mice are favored in areas with predators, perhaps because they are more difficult to see. If your hypothesis is true, what would you expect to happen in the few generations after predators are introduced to an area with a population of mice that previously did not have predators?
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Definition
| The proportion of darker colored mice will increase. |
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Term
| In what way does the human population influence evolution? |
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Definition
| Use of antibiotics by humans has selected for anitibiotic-resistant bacterial populations. | | Human development changes the habitats of many species, influencing natural selection on those species. | | Humans are responsible for the many breeds of dogs found today. |
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Term
Your arm is homologous with
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Definition
a bird wing a seal flipper |
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Term
All organisms share the same genetic code. This commonality is evidence that
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Definition
all organisms are descended from a common ancestor |
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Term
| Which of the following are fossils? |
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Definition
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Term
In Africa, there is a species of bird called the yellow-throated longclaw. It looks almost exactly like the meadowlark found in North America, but they are not closely related. This is an example of
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Definition
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Term
Which of the following are examples of vestigial structures?
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Definition
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Term
Which of the following would stop evolution by natural selection from occurring?
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Definition
| if all individuals in a population were genetically identical, and there was no genetic recombination, sexual reproduction, or mutation |
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Term
Selection against individuals at both ends of a phenotypic distribution for a character, favoring those in the middle or average of the distribution, is an example of __________.
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Definition
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Term
Body size varies among individuals in a species of lizard in the genus Aristelliger. Small lizards have a hard time defending a territory, and thus mating, but large lizards are more likely to be preyed on by owls. Therefore, natural selection favors individuals with an average body size. This is an example of _________.
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Definition
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Term
The process by which two species evolve adaptations in response to one another, such that evolutionary change in one species produces an evolutionary change in the other is called _______.
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Definition
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Term
| Which of the following selective processes did Darwin suggest to explain the evolution of the conspicuous structures and courtship behaviors that male animals use to attract a mate? |
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Definition
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Term
Which of the following is most likely to result in the evolution of altruistic behavior?
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Definition
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Term
Natural selection acts (through predation) against banded water snakes on certain Lake Erie islands, favoring the uniformly light-colored snakes. The banded form is very common on the nearby mainlands. Yet banded snakes are maintained in the island populations and not eliminated completely. This is probably due to _________.
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Definition
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Term
Genetic drift will tend to __________.
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Definition
| decrease genetic variability within populations but increase genetic variability between populations |
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Term
The Hardy-Weinberg equilibrium represents an idealized, evolution-free population in which the allele frequencies and genotype frequencies will not change over time. In order for this to happen, five conditions must be met: 1) there must be no mutation; 2) there must be no gene flow between populations; 3) the populations must be very large; 4) all mating must be random; and 5) there must be no natural selection. If one of these five conditions was violated, genetic change, and thus evolution, would occur in the populations of subsequent generations. Suppose that only condition 3 were violated—that the population was very small. In this situation, the evolution would probably be due to _________.
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Definition
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Term
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Definition
| | the total number of all the genes in a population |
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Term
| What is the Hardy-Weinberg principle |
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Definition
| a model of population genetics that shows that evolution will occur if even one of the conditions of the principle is violated |
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Term
Which of the five conditions of the Hardy-Weinberg principle describe how never-before-seen DNA can enter a population?
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Definition
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Term
Which phrase best describes the concept of natural selection?
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Definition
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Term
What type of natural selection favors individuals with rarely encountered traits over individuals with traits that are frequently encountered?
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Definition
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Term
Evolution is best defined as a change in __________.
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Definition
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Term
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Definition
| makes populations more genetically similar |
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Term
| In a mainland bird population, most individuals are black in color, and gray is a rare variation. A small group of these birds is carried by strong winds to a distant island, where they establish a new population. After a few generations, the gray phenotype is very common. What is most likely to be responsible for this? |
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Definition
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Term
| A population of insects, newly introduced to a forest, is adapting to different breeding sites: females can lay their eggs either on mushrooms on the forest floor or on the fruits of trees. In time, one group has adapted to the mushrooms, and another to the fruit. What type of selection drove these adaptations? |
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Definition
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Term
Why is the sickle cell allele found at a high frequency in African human populations?
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Definition
| | Heterozygote carriers of the allele are resistant to malaria, which has historically been prevalent in Africa. |
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Term
__________ are sequences of DNA located at specific positions of a chromosome.
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Definition
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Term
Individuals with two identical copies of a given allele are called __________ for that allele.
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Definition
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Term
When populations get very small, the danger of losing genetic variability is high. This is called a __________.
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Definition
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Term
Chance effects can change an allele’s frequency in a population. This phenomenon is called __________.
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Definition
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Term
Natural selection acts on phenotypes, which are the physical representation of an individual’s __________.
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Definition
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Term
__________ selection is a type of selection that favors individuals with average values of traits.
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Definition
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Term
Genetic drift is a ________________ process.
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Definition
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Term
Most of the 700 species of fruit flies found in the Hawaiian archipelago are each restricted to a single island. One hypothesis to explain this pattern is that each species diverged after a small number of flies had colonized a new island. This mechanism is called
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Definition
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Term
| You are studying leaf size in a natural population of plants. The second season is particularly dry, and the following year the average leaf size in the population is smaller than the year before. But the amount of overall variation is the same, and the population size hasn’t changed. Also, you’ve done experiments that show that small leaves are better adapted to dry conditions than are large leaves. Which of the following has occurred? |
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Definition
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Term
You have bacteria thriving in your gastrointestinal tract. This is an example of
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Definition
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Term
Lamarckian evolution, the inheritance of acquired characteristics, could occur
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Definition
| if the genotype was altered by the same environmental changes that altered the phenotype |
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Term
Of the following possibilities, the best way to estimate an organism’s evolutionary fitness is to measure the
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Definition
| number of offspring it produces over its lifetime that survive to breed |
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Term
According to Ernst Mayr, speciation depends on __________.
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Definition
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Term
Populations of two species living in the same areas (for example, chorus frogs and wood frogs living in the same ponds of Ohio woodlots) are said to be __________.
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Definition
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Term
The rapid speciation of Darwin's finches on the Galapagos Islands is an example of __________.
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Definition
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Term
Which of the following is the first step in the process of allopatric speciation?
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Definition
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Term
Which of the following is (are) likely to promote sympatric speciation?
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Definition
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Term
The rapid evolution of many new mammalian forms following the extinction of the dinosaurs 65 million years ago is an example of __________.
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Definition
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Term
If a haploid egg from a diploid plant is fertilized by a haploid sperm from a diploid plant, and the fertilized egg duplicates its chromosomes but does not divide into two cells, the resulting cell may then divide normally, producing an individual plant that will be _________.
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Definition
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Term
| Which of the following is (are) true of the biological-species concept? |
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Definition
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Term
| Matings among which organisms with the following sets of chromosomes would not produce offspring with the same number of chromosomes? |
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Definition
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Term
Which of the following is most characteristic of populations of different species?
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Definition
| A fertile female from one population mated with a fertile male from the other population produces no offspring. |
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Term
Which of the following is NOT an example of speciation?
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Definition
| A small group from a large mainland population colonizes a remote island. |
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Term
| Which species is at least risk of extinction? |
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Definition
| The species is composed of one large, continuous, genetically variable population |
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Term
Biologists sometimes combine two groups previously considered different species into the same species because __________.
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Definition
| | they may be physically divergent, but they are found to interbreed in nature |
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Term
__________ speciation can occur when two populations are separated by geographic space and then diverge genetically.
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Definition
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Term
__________ speciation can occur if two populations share the same geographic area but do not share habitats.
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One feature of plants that can allow them to speciate at a higher rate than other organisms is their ability to tolerate __________. This means that their gametes can contain more than one copy of each chromosome.
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__________ radiation is what can occur when one species develops into many. Usually, this occurs when a single species invades an area with many underutilized niches.
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When a species has no surviving members, it is said to be __________.
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Loss of or damage to an endangered species' __________ is one of the chief threats of extinction for these species.
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Many closely related species of marine invertebrates exist on either side of the isthmus of Panama. They probably resulted from
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Many hybrids are sterile because their chromosomes don’t pair up correctly during meiosis. Why aren’t polyploid plants sterile?
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| | They self-fertilize, using their diploid gametes. |
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In many species of fireflies, males flash to attract females. Each species has a different flashing pattern. This is probably an example of
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Under the biological-species concept, the main criterion for identifying a species is
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