bio

• Genetics


  Study of genes and heredity
• Heredity


  Passing of genetic information and traits from parents to offspring
• Gregor Mendel


  Father of genetics
• Gregor Mendel's experiment


  Focused on the observable traits of pea plants and how they pass on from generation to generation
• Genes


  Hereditary units of an organism that carry genetic material
• Alleles


  Variant form of genes
• Genotype


  The kind of gene that each progeny will have
• Phenotype


  The outward expression of the genotype
• Dominant trait


  The trait that first appears or is visibly expressed in the organism
• Recessive trait


  The trait that is present at the gene level but is masked and does not show itself in the organism
• Homozygous


  When the two alleles of the individual are the same
• Heterozygous


  When the two alleles of the individual are different
• Homozygous red = RR
• Heterozygous red = Rr
• Law of Segregation


  Each inherited trait is defined by a gene pair
• Law of Independent Assortment

  Genes for different traits are sorted separately from one another so the inheritance of one trait is not dependent on the inheritance of another
• Law of Dominance


  An organism with alternate forms of a gene will express the form that is dominant
• Codominance


  Both alleles are expressed equally in the phenotype of the heterozygote
• Incomplete Dominance


  The phenotype of a heterozygote offspring is somewhere in between the phenotypes of both homozygous parents
• Multiple Alleles


  Many genes have more than two alleles
• Polygenic Traits


  Inheritance of a trait governed by more than one gene
• Examples of polygenic traits: Hair Color, Skin tone, eye color, height, weight
• DNA (Deoxyribonucleic acid)


  The molecule that carries genetic information for the development and functioning of an organism
• DNA Replication


  The duplication of DNA during the synthesis (S) phase of the cell cycle to ensure that daughter cells have sufficient amounts of genetic material after cell division
• DNA Transcription


  The process of synthesizing an mRNA molecule on the basis of a gene sequence
• DNA Translation


  The use of an mRNA by a ribosome to synthesize a protein
• Adenine is paired with Thymine, Thymine with Adenine, Cytosine with Guanine, Guanine with Cytosine during DNA Replication
• Adenine is paired with Uracil, Thymine with Adenine, Cytosine with Guanine, Guanine with Cytosine during DNA Transcription
• Recombinant DNA


  1. Cutting or cleavage of DNA by restriction enzymes

  2. Selection of an appropriate vector

  3. Ligation of the gene of interest with the vector

  4. Transfer of the recombinant plasmid into a host cell

  5. Selection process to screen which cells actually contain the gene of interest

  6. Sequencing of the gene to find out the primary structure of the protein
• Genetic Engineering


  The process of using recombinant DNA (rDNA) technology to alter the genetic makeup of an organism
• Genetic Engineering involves the introduction of new traits, enhancement of a present trait by increasing the expression of the desired gene, or enhancement of a present trait by disrupting the inhibition of the desired genes' expression
• Recombinant DNA


  A molecule of DNA that has been modified to include genes from multiple sources, either through genetic recombination or through laboratory techniques
• Insulin production using Genetic Engineering

  1. Scientists remove DNA from a human cell nucleus and plasmid DNA from a bacterial cell

  2. The desired gene is removed from the human DNA and recombined with plasmid DNA

  3. The plasmid is put back into bacteria

  4. Scientists grow colonies of bacteria in special vessels

  5. Scientists remove the desired proteins from the cells-in this case, insulin

  6. The insulin is purified and, then, is available for human use
• The diversity of life on Earth today is the result of evolution
• During the Archean Eon the first stirrings of life began
• During the Proterozoic life evolved from simple bacteria having prokaryote cells, first to more complex single celled organisms, the eukaryotes, and then to multi-celled plants and animals
• The earth's atmosphere was transformed by cyanobacteria, the first to use photosynthesis, and over time the atmosphere became oxygenated
• The first plants and fungi appeared during the Proterozoic
• Paleozoic Era


  The age of invertebrates, when life was primitive and included many invertebrates, the earliest fish and amphibians
• Mesozoic Era


  The age of reptiles, the time of the dinosaurs