Protein Synthesis and Genetic Engineering

PROTEIN SYNTHESIS AND GENETIC ENGINEERING STUDY NOTES

PART 1: MOLECULAR STRUCTURE

  • DNA vs RNA Differences
    • Characteristic Comparison: Determine if statements apply to A. DNA Only, B. RNA Only, C. Both DNA and RNA, or D. Neither.
    1. A is usually double-stranded (A: DNA Only)
    2. Contains cytosine and adenine (C: Both DNA and RNA)
    3. Contains the sugar ribose (B: RNA Only)
    4. Is coiled in a double helix (A: DNA Only)
    5. Contains adenine and uracil (B: RNA Only)
    6. Is present in the nucleus (A/C: Both DNA and RNA)
    7. Is present in the cytoplasm (B: RNA Only)
    8. Is usually single-stranded (B: RNA Only)
    9. Contains the sugar deoxyribose (A: DNA Only)
    10. Contains phosphate groups (C: Both DNA and RNA)
    11. Is directly related to translation (B: RNA Only)
    12. Is directly involved in transcription (C: Both DNA and RNA)
    13. Contains guanine and thymine (A: DNA Only)
    14. Is involved in replication (A: DNA Only)

PART 2: PROTEIN SYNTHESIS PROCESS

  • Processes Defined
    • Transcription
      • Definition: DNA is copied to mRNA by RNA Polymerase.
      • Location: Nucleus.
    • Translation
      • Definition: mRNA is read by ribosomes, tRNA brings the correct amino acids matching codons to their corresponding anticodons, linking amino acids together into proteins.
      • Location: Ribosome/Cytoplasm.
  • Codon: A sequence of 3 bases on mRNA that codes for an amino acid.
  • Gene: A section of DNA that codes for a protein.
  • Mutation: A change to a DNA sequence including insertion, deletion, or substitution.

PART 3: GENETIC CODE AND AMINO ACIDS

  • Genetic Information
    • A human cell contains approximately 20,000 genes.
    • Human cells contain 46 chromosomes (23 pairs).
  • Gene Expression
    • Identical cells (skin, nerve, liver) may function differently due to environmental factors affecting gene expression; only certain genes being turned on.
  • Alleles and Traits
    • Unique traits arise from different alleles inherited.
    • Example: Different hair colors due to variations in alleles.

PART 4: ORDER OF PROTEIN SYNTHESIS STEPS

  • Correct Order of Protein Synthesis Statements:
    1. DNA strands unwind at the location of a gene (D)
    2. RNA bases pair up with the DNA and copy the gene's instructions forming mRNA (B)
    3. The mRNA strand leaves the nucleus and attaches to the ribosome (A)
    4. Amino acids are linked together by peptide bonds (E)
    5. The chain of bonded amino acids breaks free from the ribosome (C)

PART 5: FUNCTIONS OF DNA AND PROTEINS

  • Function of DNA: Code for proteins.
  • Function of Proteins: Enzymes speed up reactions, provide structure.
    • Example: Enzymes facilitating metabolic reactions.
  • Different Types of Amino Acids: There are 20 different amino acids.

PART 6: DNA SEQUENCES AND PROTEIN CODE

  • Example DNA to mRNA Sequence:
    • Given DNA: TAC CTA GCA GCC TAA GGA
    • mRNA: AUG GAU CGU CGG AUU CCG
    • Codons in mRNA: 6 codons.
    • Amino Acids: Met-Asp-Arg-Arg-Ile-Pro
  • Gene Length Calculation: If a polypeptide is 100 amino acids long, the gene length is calculated as:
    • 100 imes 3 = 300 bases.

PART 7: MUTATIONS AND DNA ALTERATION

  • Types of Mutations:
    • Types Identified:
    • Deletion
    • Insertion
    • Substitution
  • Effect of Radiation on Mutations: Increasing exposure can raise the mutation rate in bacterial cultures.

PART 8: GEL ELECTROPHORESIS

  • Conclusion Based on Gel Results: The analysis can determine parent-child genetic relationships by comparing DNA bands.

PART 9: ENVIRONMENT AND GENETIC EXPRESSION

  • Environmental Influence: Example with goldfish growth influenced by surroundings.
  • Trait Expression in Relation to Environment: Changes in pigmentation in hammerhead sharks due to light exposure.

PART 10: ETHICS AND GENETIC ENGINEERING

  • Cloning and Genetic Engineering Issues:
    • Ethical considerations surrounding cloning humans and the potential outcomes of genetic modification.
  • Transgenic Organisms: The creation of genetically modified organisms such as goats producing human proteins.

CONCLUSION: UNDERSTANDING PROTEIN SYNTHESIS

  • Summarize Key Takeaways: Protein synthesis and genetic engineering are fundamental biological processes that involve complex interactions of DNA, RNA, and environmental factors influencing gene expression. Understanding these processes is crucial for advancements in biotechnology and medicine.