Summary and Exam Tips for Genetic Modification
Genetic Modification is a subtopic of Biotechnology and genetic modification, which falls under the subject Science in the IB MYP curriculum. Genetic engineering involves altering the genetic material of an organism by removing, changing, or inserting individual genes from another organism, resulting in a genetically modified or transgenic organism. The DNA that now includes genes from another organism is called recombinant DNA. Examples include inserting the human insulin gene into bacteria for insulin production, and modifying crops like wheat and maize to resist pests and herbicides or to enhance nutritional content, such as golden rice which is enriched with vitamin A.
The process of genetic engineering involves isolating the desired gene using restriction enzymes, creating sticky ends. A bacterial plasmid is cut with the same enzyme, and DNA ligase joins the gene and plasmid. The engineered plasmid is inserted into bacteria, which reproduce and express the gene. Bacteria are ideal for this due to their simple genetic code, lack of ethical concerns, and the presence of plasmids.
Advantages of genetically modified crops include reduced pesticide use, lower production costs, and increased yields. However, disadvantages include potential allergic reactions, lower nutritional value, and increased toxin levels.
Exam Tips
- Use precise Biology terms: Avoid vague words like "it" or "they" without context. Clearly define terms such as transgenic organism or recombinant DNA.
- Understand the question: Differentiate between 'what' and 'why' questions. For example, don't provide definitions when asked for explanations.
- Consider mark allocation: The number of marks indicates the depth of response required. Write concise yet comprehensive answers.
- Practice with examples: Use examples like human insulin production in bacteria or golden rice to illustrate your understanding.
- Stay organized: Structure your answers logically, starting with definitions, followed by examples, and concluding with advantages and disadvantages.
