Question | Answer |
4 sub-disciplines of modern genetics | Transmission genetics, molecular genetics, population/evolutionary genetics, quantitative genetics |
Transmission genetics | Study of how traits are passed on from one generation to the next. Mendelian/classical |
Molecular genetics | Study of the chemical nature of genes and how they operate at a molecular level |
Population/ evolutionary genetics | Study of genetic variation within and among populations |
Quantitative genetics | Study of heredity of traits in groups of individuals where many genes determine traits simultaneously |
Alleles | Alternate forms of a gene at a locus |
Principle of segregation | Genes come in pairs (diploid) and when gametes are produced each gets one gene (haploid) at random from each gene pair, but not both |
Chromosomal theory of inheritance | Chromosomes carry genes |
Thomas Hunt Morgan | Fruit flies. Sex-linked inheritance. First evidence for chromosomal theory of inheritance. Genes arranged linearly on chromosomes. |
Recombinant | New combination of alleles not seen in parents |
Barbara McClintock | Detected recombination by studying maize under a microscope |
Friedrich Miescher | Discovered DNA. Collected white blood cells from pus, lysed them and isolated nuclei. Found nuclein, high in phosphorous. |
Griffith | S-strain virulent, R-strain nonvirulent. Bacteria and mice. Chemical substance from a cell genetically transformed other cells. |
Oswald Avery | Went further with Griffith's experiment; DNA is transforming principle, not RNA or protein |
Beadle and Tatum | Used mold to prove Garrod's idea of relationship between genes and enzymes. One gene-one enzyme |
One gene- one polypeptide | Each gene codes for only one polypeptide, but each polypeptide is coded for by more than one gene |
Watson and Crick | Stole Roseline Franklin's research to build a model of DNA (double helix) |
Purines | Adenine, guanine |
Pyrimidines | Cytosine, thymine |
Three forms of DNA | A, B, Z |
Gene expression | Process by which a gene produces its product and the product carries out its function |
What does uracil replace? | Thymine. Only in RNA |
Transcription | DNA splits, RNA polymerase makes mRNA copy |
Translation | mRNA carries instructions to ribosomes and a protein is assembled |
Genetic code | mRNA code, not a DNA code |
Point mutation | Change one base to another (sickle cell) |
indel mutation | Insertion and deletion of pieces of DNA |
Frameshift mutation | single insertion or deletion that alters the order the codons are interpreted in |
Hardy-Weinburg | Genetic equilibrium in a population |
Recombination | Crossing over of homologous chromosomes during meiosis |
Khorana and Niremberg | determined nature of genetic code (codons) |