Bio CH3

  1. Central dogma of molecular biology
    DNA makes RNA which makes proteins
  2. Transcription
    When DNA makes RNA
  3. Translation
    When RNA makes proteins
  4. 1 example of a modification to the central dogma
    HIV(retrovirus) - can convert their RNA genome into a DNA copy via reverse transcriptase (which is an eznyme)
  5. What 3 things do nucleotides have
    • phosphate group
    • sugar
    • nitrogenous base
  6. Difference in sugars in DNA and RNA
    DNA has doxyribose sugar where RNA has just ribose sugar
  7. What 4 nitrogenous bases make up DNA
    • Cytosine
    • Thymine
    • Adenine
    • Guanine
  8. What 4 nitrogenous bases make up RNA?
    • Cytosine
    • Uracil
    • Adenine
    • Guanine
  9. What are the three nitrogenous bases that are pyrimidines?
    • Cytosine
    • Thymine
    • Uracil
  10. What 2 nitrogenous bases are purines?
    • Adenine
    • Guanine
  11. What do purines do
    Production of RNA and DNA, proteins and starches, the regulation of enzymes and cell signaling.
  12. What do pyrimidines do?
    Production of RNA and DNA, proteins and starches, the regulation of enzymes and cell signaling.
  13. What bonds link 2 sugars at the 3 prime and 5 prime carbons?
    Phosphodiester Bonds
  14. In what direction is the sequence of bases always written?
    5 prime (phosphate) to 3 prime end (hydroxyl carbon) end
  15. What three things are required for DNA replication?
    • 1. Something to copy (a template)
    • 2. Something to perform the copy (DNA polymerase)
    • 3. The building blocks to make copies (nucleotides)
  16. What are the ends of the X's of chromosomes called?
    Telomeres (have to do with aging)
  17. What is the first stage of the central dogma?
    Transcription. DNA is transcribed into an RNA transcript
  18. What is the second stage of the central dogma?
    RNA Processing. In eukaryotes, the RNA transcript is spliced and modified to produce mRNA, which moves from the nucleus to the cytoplasm
  19. What is the third stage of the central dogma?
    mRNA leaves the nucleus and attaches to the ribosome.
  20. What is the fourth stage of the central dogma?
    Amino Acid activation. Each amino acid attaches to its proper tRNA with the help of a specific enzyme and ATP.
  21. What is the 5th stage of central dogma?
    Translation. A succession of tRNAs add their amino acids to the polypeptide chain as the mRNA moves through the ribosome, one codon at a time. (When completed the polypeptide is released from the ribosome)
  22. Where does mRNA transcription occur?
    Within the nucleus
  23. Intron
    is intervening DNA sequences that interrupt the sequence of a gene
  24. Exon
    • The coding sequences that are
    • expressed
  25. Eukaryotic pre-mRNA splicing
    • •Small
    • nuclear ribonucleoprotein
    • particles (snRNPs)
    • composed of snRNA and
    • protein recognize
    • and excise introns from pre-mRNA transcript, creating the final mRNA transcript
  26. What are the 4 sites of the ribosome
    • mRNA binding site
    • A site (Aminoacyl-tRNA binding site)
    • P Site (Peptidyl-tRNA binding site)
    • E site (Exit site)
  27. Summary of Gene Expression (3 main points)
    • 1. An mRNA copy of a gene is produced during transcription
    • 2. The mRNA is used to synthesize protein during translation
    • 3. Converts the information in the genotype into the phenotype
Card Set
Bio CH3