Hardy Weinberg Equation
- p=gene frequency of the dominant gene
- q=gene frequency of the recessive gene
- p2=percentage of homozygous dominant individuals
- q2=percentage of homozygous recessive individuals
- 2pq=percentage of heterozygous individuals
- It works best for populations where the gene pool stays constant. The criteria are:
- 1. Large population
- 2. No mutations occurring within the population
- 3. Elimination of gene flow so other populations of the
- same species should be isolated.
- 4. Random mating within population
- 5. NO natural selection occurring
- The branch of mathematics that predicts the
- chance that a certain outcome will occur. Probability is used to predict the
- outcomes of a certain genetic cross.
Process by which a tube forms between two bacteria and one gives its plasmid to the other. If the receiving bacterium has no plasmid, the donated plasmid stays as is. If there is a plasmid in the receiving bacterium, the two fuse to create a new plasmid.
Process by which unassociated ("naked") pieces of DNA are taken into a bacterium and incorporated into the genome.
Process by which DNA is injected into a bacterium and becomes a part of the bacterium's DNA. This is common with viruses, in which case the bacterium proceeds to make copies of the virus and lyse itself.
Bacteria-only enzymes that cuts up foreign DNA, protecting bacteria from DNA of phages and other viruses. Function by locating a specific base sequence in the DNA and cutting there. This, along with gel electrophoresis, enables analysis of genes (such as DNA fingerprinting).
Makes strong covalent bonds between the ends of two molecules after weak hydrogen bonds are set in place. Often used to join sticky-ended DNA strands after the DNA has been cut by restriction enzymes, thus forming recombinant DNA. Also, it is essential for DNA replication.
"Restriction Fragment Length Polymorphisms:" The differences in homologous DNA sequences that are reflected in differing lengths of DNA fragments produced when the DNA is cut by restriction enzymes. This is the idea behind DNA fingerprinting.
"Polymerase Chain Reaction:" Technique by which any segment of DNA can be copied quickly and precisely. This allows for small amounts of tissue to be used in DNA fingerprinting. The DNA sample is mixed with loose nucleotide monomers and DNA polymerase. This is first heated to separate the DNA strands then cooled so that the separate DNA strands form complementary strands from the loose nucleotides.
Gel Electrophoresis is a technique used for separating and purifying macromolecules, specifically DNA. The DNA is placed in a solution in wells near the negative end of the gel. The DNA molecules will move towards the positive side because they are negatively charged. The larger DNA fragments do not move as far due to friction. This enables scientists to compare genes using RFLPs.
Organisms that contain genes from other species.
Sticky ends are formed when a DNA strand is cut jaggedly by a DNA strand. They allow the DNA strand to be spliced to another DNA strand if the other DNA strand has a sticky end with a complementary sequence to the sticky end of the original. DNA cut by the same restriction enzyme will have complementary sticky ends.
Formed when a DNA strand is cut clean, without any side sticking out. They are not sticky because they are no one-stranded portions of DNA that could be matched up with other sticky ends.
Producing genetically identical copies of a cell, organism, or DNA molecule.
The way in which an animal's mitochondria is solely derived from that of the mother. This is because the middle piece of the sperm, with all of its mitochondria, never actually enters the egg cell.
Arranging photos of DNA chromosomes taken during Metaphase into matching pairs to discern any chromosomal abnormalities and to learn the gender of the subject.
DNA is taken from two different sources and spliced together, using DNA ligase to join the strands where the sticky ends are complementary. The resulting DNA molecule is recombinant.
Plasmids contain some of a bacterium's genetic information. Plasmids are sometimes called plasmid vectors due to their ability to transfer the genes they contain from one cell to another.
A virus that inserts its DNA into a bacterium, eventually causing the bacterium to reproduce the virus and lyse.
The DNA of a phage, such as a bacteriophage
Viral replication cycle resulting in release of new viruses by lysing of the cell.
A type of infection in which a virus embeds its DNA into the host cell's DNA and then is replicated along with the rest of the cell's DNA. After some time, the viral DNA separates from the DNA of all of the cells it has infected and takes the steps a lytic infection would take.
Changes in the gene pool of a population resulting from chance. This is a form of microevolution that has the potential to eliminate certain alleles from small populations by chance.
When a new population is established with a different genetic pool than that of its previous population. This form of microevolution often results from migration.
Genetic drift resulting from a vast reduction in population size. This is a form of microevolution.
A gene pool that has been altered due to migration of individuals into and out of the gene pool. This is a form of microevolution.
Changes in the nucleotide sequence of DNA that is the ultimate source of genetic diversity. This is a minute form of microevolution.
The main factor affecting gene pools, because increased reproductive success leads to increased allele frequency. This cannot be accurately accounted for, and so probability is less useful in predicting trends in the gene pool of populations experiencing this phenomenon.
Evolution on a large scale, such as speciation, adaptive radiation (divergent evolution), and extinction.
Changes in the gene pool of populations over generations.
Adaptations in one species act as a selective force on a second species, causing the two species to evolve "together."
Model of evolution in which speciation occurs in short bursts, between which are periods of stability in the gene pool.
A model of evolution in which evolution occurs constantly, but slowly.
Reproductive characteristics that prevent species from combining.
- These prevent mating & fertilization from occuring. The four are:
- *Can be remembered by the word THuMB
Time based prezygotic barrier that states that two species cannot mate because their mating seasons are at different times.
Although the two species do not live far from one another and might be coitally compatible, they do not mate due to their habitats (ex. garter snakes on land, relatives in water cannot mate)
Different species are prezygotically blocked due to different mating behaviors. This can include scents, dances, calls, etc.
Male, female sex organs are incompatible; or gametes cannot fuse.
Mechanisms that prevent the results of interspecies mating from being successful, preventing the development of a combined species. Hybrid Inviability and Hybrid Sterility
When the offspring dies prior to being able to reproduce, thus preventing the hybrid from being reproductively successful.
When the offspring is successful in survival but not in reproduction.
Evolutionary process by which sexually attractive traits become more common in a gene pool. This is separate from natural selection because natural selection selects for survivally attractive traits.
A variation in a trait of individuals that coordinates with some gradual change in temperature or other factor
Initial block to a gene flow is a geographic barrier that physically isolates the populations.
Origin of a new species without geographic isolation.
Individuals at one end of the curve have higher fitness at the middle or other end. As a result, the curve usually moves so that these individuals make up most of the population.
Takes place where individuals have higher fitness at the center of the curve compated to the individuals at either end. As a result, the curve becomes steeper.
Individuals at the upper and lower ends of the curve have higher fitness than individuals in the middle. As a result, two "curves" appear - one for one form of the trait, and another for the opposite, with a "valley" in between the two.
Evidence for Evolution
- Fossil Record
- Comparative Anatomy
- Molecular Biology
Similarity among body parts that imply a common ancestor.
Similarity of a structure between two unrelated species due to convergent evolution.
Adaptive change resulting in analogous similarities between organisms. Species of different lineages come to resemble one another as a result of living in similar environments.
Also referred to as Adaptive Radiation, this is the way in which two species came from a common ancestor yet grew different due to environmental pressures.
The branch of biology concerned with identifying, naming, and classifying species
Hierarchy of Classification
- *Dear King Philip Came Over For Good Spaghetti
A group of organisms that are able to breed together and look very similar.
Spontaneous Generation Theory
Incorrect notion that life can come from an inanimate material.
Formed as a result of protein ionizing and attracting polar water. Were not able to replicate themselves, but could store and pass on nucleic acids.
Atmoshpere of the early Earth, which had no free oxygen.
Complex experiment that proved that Earth's early atmosphere could have produced organic compounds as a result of lightning.
Hypothesis that states that life could have resulted without a "divine nudge" or existence of life on other planets. The organic components formed as a result of lightning (acting upon the early atmosphere) and arranged themselves into units that would later be the source of life.
CREDIT FOR DEFINITIONS GOES TO LUKE