What is a gene?Accurate Replication | Proof-reading enzymes | General Stability | Double helix = prevents breaks and mutations | Information Storage | Nitrogen bases code for amino acids and proteins | Transmission Information | Transcription & Translation |
History1866; Gregor Mendel | Discovered factors (genes), come up with three laws of hereditary | 1900; Corren, Tschermak, and Devries | Lead to the rediscovery of Mendel | 1900; Robert Feulgen | Came up with DNA stain, "feulgen stain" stains red | 1902; Sutton and Boveri | Chromosomal theory of inheritance -> genes are located on chromosomes, narrowed down gene location | 1925; Fred Griffith | Studied two type of bacteria. smooth (pathogenic) vs. rough (harmless), lead to the discovery of transformation (the ability of bacteria to pick up and use genetic material) which allows genetic engineering | 1930s; Collection of Scientists | Eukaryotic chromosome is 80% protein (where most looked), and 20% DNA, prokaryotic DNA is 100% DNA | 1944; Avery, Macleod, and McCarthy | Used enzymes to destroy different proteins and genetic material, concluded that DNA is the genetic material | 1950s; Alfred Hershey and Martha Chase | Radioactively tagged DNA and proteins in bacterial phages, concluded that DNA can be transformed (confirmed Griffith) | 1950s; Chargaff | Amount of A = Amount of T, Amount of C = Amount of G (Chargaff's Rule) | 1953; Watson, Crick, Wilkins, and Franklin | Discovered the structure of DNA | 1983; Barbara McClintock | Discovered transposons (jumping genes) | 1992; W.F. Anderson | Human gene therapy with human growth hormones | 1992; Kary Mullis | PCR (Polymerase chain reaction) |
Crick's DiscoveryTelomeres | "Cap" of DNA, keeps it from splitting | Double helix | Allows DNA to be stable | Distance between base pairs | .34 nm | Complete turn | 3.4 nm, 10 base pairs | Length of DNA molecules | 2 meters | Width of DNA molecules | 3 nm | Polymer | Made up of nucleotides | Nucleotides are made up of... | Ribose sugar (5C), a phosphate group, and a nitrogen base (A, T, G, C) | DNA is... | Antiparallel |
RNA Structure- Single strand
- Ribose sugar (OH on 2')
- Nitrogen bases = A, U, C, G |
| | Central DogmaDNA -------> | RNA ---------> | Proteins |
3 Theories of DNA ReplicationConservative | 1 completely new double helix, 1 completely new | Semi-Conservative | Double helixes are 1/2 new, 1/2 old | Dispersive | Different parts of the double helix are new and old | Meselson & Stahl | Proved DNA replication was semiconservative using bacteria cultures and nitrogen isotopes |
DNA ReplicationLeading Strand | 5' - 3' | Lagging Strand | 3' - 5' | 1) Topiosomerase | Relieves stress, DNA will not break | 1) Helicase | Unzips/uncoils DNA, opens double helix into leading and lagging strand | 2) Binding Proteins | Keeps the replication fork open | 3) DNA Polymerase | Adds nucleotides to the leading strand 3' - 5' | 4) Primase | Adds a RNA primer for nucleotide fragments (Okazaki fragments) | 5) DNA Polymerase | Will connect to primase, adds nucleotides in 3' - 5' | 6) DNA Ligase | Connects the new nucleotides from DNA polymerase to primer on 5' end, changes primer to DNA | 7) Proof Reading Enzymes | Checks base pairs (A-T, C-G) |
DNA TranscriptionMaking of a mRNA molecule (5' - 3') from a 3' to 5' DNA molecule | 1) Transcription Factors (Proteins) attach to a regulatory gene (TATA box) | 2) RNA Polymerase will bind to transcription factors, open up DNA | 3) RNA Polymerase will add nucleotides of RNA to form a mRNA molecule, mRNA will hang off of the RNA polymerase | 4) Once RNA reaches a stop codon on the DNA; 1) mRNA leaves 2) polymerase moves to the next gene 3) DNA closes | Introns | Junk DNA | Exons | Leaves nucleus | Poly-A Tail | 3' end of mRNA, protects nucleotides |
DNA TranslationSynthesize a protein using mRNA, rRNA, tRNA, and amino acids | 1) First tRNA (amino acid) enters P sire, codon and anti codon are complementary | 2) 2nd tRNA (amino acid) enters A site | 3) Amino acid on P site forms a peptide bond with the amino acid in the A site | 4) RIbosome moves down 1 codon, tRNA remains stationary | RNAi | Turning off a gene by using a complementary mRNA strand to block mRNA from translation |
| | Genetic Code4 bases x triplet code = 64 possible combinations | 1 start code (AUG), 3 stop codons | Many codons equaling 1 amino acid buffers against mistakes |
Characteristics of Genetic CodeTriple Code (Codons) | Commaless = no breaks inbetween | Non-Overlapping | Punctuation, stop and start codons | Degenerate = Some amino acids have more than one code | Unambiguous = Same genetic code can be used in different organisms |
Types of MutationsDeletion | Lose a base pair | Addition | Base pair is added | Substitution | Different base pair is added | Non-Disjunction | Wrong chromosome number, occurs in cell division, caused when mitotic spindles break |
BiotechnologyNorthern Blotting | Electrophoresis of RNA | Southern Blotting | Electrophoresis of DNA | PCR (Polymerase Chain Reaction) | 1) Take DNA sample less than 2,000 pairs 2) Place in test tube with TAQ polymerase and nucleotides 3) Heat tube then cool, heat shock for 7-9 minutes, problem = no proof reading enzymes | Genetic Engineering/Recombinant DNA | Need a target and a vector (usually bacterial plasmid) | Transgenic Animal | Introducing a gene from an animal into the genome of another species |
|
Created By
Metadata
Comments
No comments yet. Add yours below!
Add a Comment
Related Cheat Sheets
More Cheat Sheets by isabellagates