Genetics study of biologically inherited traits, including traits that are influenced in part by the environment Genomics study of all the genes in an organism to understand their molecular organization, function, interaction, and evolutionary history Genes Elements of heredity that are transmitted from parents to offspring in reproduction Deoxyribonucleic acid DNA - material genes are made of uses deoxyribose as the sugar double stranded helix antiparallel Ribonucleic Acid RNA - used in part of the process of creating needed molecules based off of the genes in DNA single stranded helix Ribose is the sugar Nitrogenous Base One component of a nucleotide 4 Nitrogenous bases in DNA: Adenine, Guanine, Tyrosine, Cytosine Nucleotide a molecule consisting of a phosphate, sugar, and base Phosphodiester Bonds Covalent bond formed between the 5' phosphate group of one nucleotide with the 3' hydroxyl group of the next nucleotide in line These bonds form the backbone of a nucleic acid molecule (aka DNA, RNA) Purine An organic base found in nucleic acids; Adenine and Guanine Pyrimidine An organic base found in nucleic acids; Cytosine, Thymine (in DNA), and Uracil (in RNA) Hydrogen Bonds A weak noncovalent linkage between two negatively charged atoms in which a hydrogen atom is shared Guanine A purine base in DNA and RNA Bonds only with Cytosine Cytosine A pyrimidine base in DNA and RNA Binds only with Guanine Adenine A purine base in DNA and RNA Binds with Thymine in DNA or Uracil in RNA Thymine A pyrimidine base found only in DNA Binds with Adenine Uracil A pyrimidine base found only in RNA Binds to Adenine in a RNA strand Nucleic Acid A polymer composed of repeating units of phosphate-linked five-carbon sugars to which nitrogenous bases are attached Antiparallel Where one string of nucleotides runs one direction and pairs with another string of nucleotides running in the opposite direction Chemical orientation of the two strands of a double-stranded nucleic acid molecule; the 5'-3' orientation of the two strands are opposite each other Auxotroph A mutant microorganism unable to synthesize a compound required for its growth but able to grow if the compound is provided Phototroph An organism able to grow in minimal medium without any added help Phenotype The observable properties of a cell or an organism, which result from the itneraction of the genotype and the environment. Genotype The genetic constitution of an organism or virus, typically with respect to one or a few genes of interest, as distinguished from its appearance, or phenotype Minimal Medium A growth medium consisting of simpe inorganic salts, a carbohydrate, vitamins, organic bases, essential amino acids, and other essential compounds Complete Medium Culture medium containing all required nutrients to support growth and cell division Genetic Block Caused by a mutation that makes it impossible for the organism to produce a specific needed protein by halting the biosynthetic pathway Deoxyribose Sugar in DNA Ribose Sugar in RNA Leading strand The DNA strand whose complement is synthesized as a continuous unit DNA Polymerase an enzyme that catalyzes the synthesis of DNA from deosynucleoside 5' triphosphates using a template strand Helicase Separates the stands of DNA Gyrase A topoisomerase enzyme that helps to relax the tension in the coils during DNA replication Primer RNA primer of 2-5 bases that start DNA synthesis SSB binds single stranded DNA Lagging Strand The DNA strand whose complement is synthesized in short fragments later joined together Endonuclease breaks internal phosphodiester bonds in DNA or RNA Exonuclease An enzyme that removes a terminal nucleotide in apolnucleotide chain by cleavage of the terminal phosphodiester bond RecA protein Unwinds dsDNA and helps insert ssDNa and promotes replacement of homologous chromosomes Ligase An enzyme that catalyzes formation of a cobalent bond between adjacent 5' P and 3' OH termini in a broken polynucleotide strand of double stranded DNA Mismatch repair enzyme Fixes a mismatched pair by choosing a strand and replacing the mismatched base with the correct base Synaptonemal complex formed during substage of first meiotic prophase and binds together homologous pairs of chromosomes during synapsis prophase of meiosis