Regents Review Day 5 Unit 9: Biotechnology Unit 10: Evolution

73.Selective breeding is when organisms are picked to mate with other organisms because of certain desirable traits (farmers pick cows because of their ability to produce milk) a.May lead to good traits from both organisms combining to create a more desirable trait

74.Selective breeding only works within the same species a.If organisms of similar but not the same species are able to breed, the offspring usually are sterile (can’t reproduce), Ex. Mule (Horse x Donkey) Donkeys have 62 chromosomes (31 pairs) Horses have 64 chromosomes (32 pairs) Mules have 63 chromosomes!

75.DNA is cut using Restriction enzymes (specific to specific sections of DNA – ex. AATTA) a.Short single stranded leftover pieces of DNA remain at the cut ends, “sticky ends”

76.Genetic engineering – use of tools to modify the DNA sequences (genetic code) of an organism a.Removal of a gene or genes from one organism and adds them to the genes of another organism (ex. GloFish or Insulin producing Bacteria)

77.Insertion of recombinant DNA into bacterial cells will allow them to produce new proteins a.Recombinant plasmids are small circles of bacterial DNA that have been cut open and had a segment of DNA containing a gene from another organism b.Organism can now create the protein the is coded by the inserted gene

78.Plants that have been genetically engineered have recombinant plasmids inserted into their cells that alter the genes of the organisms a.Transgenic organism – term used to refer to an organism that contains genes from other organisms

79.Clone – genetically identical cells produced from a single cell

80.Gel Electrophoresis is a technique used to separate fragments of cut DNA according to size a.The bands at the bottom contain the smallest portions of DNA because the smaller fragments move more easily b.The banding pattern is the position of the different sized strands of DNA in the gel c.This can be used to locate similarities in DNA between two organisms

81.DNA Fingerprinting – Analyzes a collection of DNA fragments and is used to determine whether two samples of genetic material are from the same or similar people a.The more bands of DNA in common the closer in relation they are to each other b.If two lanes show the same pattern of DNA bands, the two samples are identical

82.Evolution is the process of change over time

83.Organisms have different structural adaptations to carry out essential life functions a.Adaptations are inherited traits that can increase an organism’s ability to survive and reproduce (ex. Camouflage, mimicry (coloring that mimics another dangerous organism), or poison)

84.Homologous Structures – animals that have similar structures (bones) but have different functions a.Arm of a human and the flipper of a whale are homologous structures b.Indicates a Common Ancestor

85.Analogous Structure – structure have the same function but are not the same structure a.Wings of birds and insects are different, yet do the same things

86.Vestigial Structure – structures are smaller size or reduced in function in current organisms, but may have been functional in distant ancestors a.Ex. Wings on Penguins, Femur in whale, appendix in humans

87.Comparative Embryology – comparing the development of structures occur in the same order and in similar patterns of related groups

88.Comparative Biochemistry – comparing the chemicals in living organisms a.The more similarities between chemicals = the more closely related

89.Natural selection is the process that may lead to the evolution of a new species a.is the process by which organisms with variations most suited to their local environment survive and leave more offspring

b.Ecosystems allow the most fit organisms to survive and reproduce, their genes are passed on to their offspring, which may lead to a new species (over much time) i.Ex. Antibiotic resistant bacteria, insecticide resistant insects, and the peppered moth in England c.Survival of the Fittest – organisms best adapt for their environment are more likely to survive, therefore reproduce, and pass on beneficial genes to their offspring

90.The fossil record provides evidence that evolution has occurred a.Fossils show patterns of structural change that indicate extinct species are related to currently living species

91.The first living organisms were single celled prokaryotic organisms a.The fossil record shows that simple prokaryotic cells evolved into more complex prokaryotic cells over time

92.The rate at which evolution occurs varies from organism to organism a.Some organisms are more affected by certain fluctuating environmental changes than others

93.The allele frequency (gene frequency) in a population is the percentage of alleles for a specific characteristic a.If a characteristic benefits the survival of individuals in a population, it’s frequency in the population will increase

94.Reproductive Isolation – separation of a species or population so that they no longer interbreed a.When a small group of individuals is separated from a main population, they may evolve into a new species that is specialized for a different environment, or become extinct b.Changes in genes result in variations that lead to the formation of a new species c.Genetic change is the mechanism that drives evolution

95.Genetic variation within a population is important because it allows the a population to adapt to changing environmental conditions a.Mutation, gene recombination (sexual reproduction), and lateral gene transfer are sources of genetic variation for evolution

96.Changes in genes make evolution possible a.New genes can arise from DNA mutations

97.If a population has a high degree of genetic diversity, it gives the population an increased ability to adapt if the environment ever changes dramatically 98.As long as genes that result in favorable characteristics exist in a population, the species will not become extinct in an environment