IB MYP 4-5 Biology-Genetic Modification- Study Notes - New Syllabus
IB MYP 4-5 Biology-Genetic Modification- Study Notes – New syllabus
IB MYP 4-5 Biology-Genetic Modification- Study Notes – IB MYP 4-5 Biology – per latest IB MYP Biology Syllabus.
Key Concepts:
- Stages of development in organisms
- Metamorphosis (complete vs incomplete)
- Human life cycle from zygote to adult
Biotechnology: Genetic Modification & Recombinant DNA Technology
What Is Biotechnology?
Biotechnology is the use of living organisms or their parts (like cells, enzymes, or DNA) to create useful products for medicine, farming, or industry. It connects biology with technology improving crops, curing diseases, and solving real-world problems.
What Is Genetic Modification (GM)?
Genetic Modification means changing the DNA of an organism by adding, removing, or altering genes to give it new traits — like faster growth, resistance to disease, or better nutrition.
Common Examples of GM Organisms
| Organism | Modified For… |
|---|---|
| GM Corn | Pest resistance (reduces pesticide use) |
| Golden Rice | Vitamin A to prevent blindness |
| GM Cows | More or disease-free milk |
| GM Bacteria | Produce insulin for diabetes patients |
What Is Recombinant DNA Technology?
Recombinant DNA (rDNA) technology combines DNA from two different sources to create new genetic combinations. It is the main technique used in genetic modification.
Steps in Recombinant DNA Process
- Identify the gene to transfer (e.g., insulin gene)
- Cut the gene using restriction enzymes
- Insert the gene into a vector (like a plasmid)
- Transfer the vector into a host organism (e.g., bacteria)
- Host multiplies and produces the desired product
Example: Bacteria Making Human Insulin
- Human insulin gene is cut and inserted into bacterial plasmid
- Bacteria read the gene and produce human insulin
- Insulin is then collected, purified, and used in medicine
Uses of Genetic Modification
| Field | Application |
|---|---|
| Medicine | Insulin, growth hormones, vaccines |
| Agriculture | Pest-resistant crops, faster growth |
| Environment | GM bacteria to clean oil spills |
| Industry | Enzymes in detergents, food processing |
Ethical and Safety Concerns
| Concern | Explanation |
|---|---|
| Health effects | Unknown long-term effects of GM food |
| Cross-contamination | GM genes spreading to wild plants |
| Playing with nature? | Moral concerns about altering life |
| Corporate control | Big companies may control food supply |
Benefits of Genetic Modification
- Increases food production
- Reduces need for chemical pesticides
- Makes life-saving medicines faster
- Solves global issues like malnutrition and disease
Biotechnology uses genetic tools like recombinant DNA to solve big problems in farming, health, and the environment. Genetic modification can improve lives – but it must be done carefully, ethically, and sustainably.
CRISPR-Cas9 Gene Editing
What Is CRISPR-Cas9?
CRISPR-Cas9 is a revolutionary gene-editing tool that allows scientists to cut and modify DNA at precise locations – like a pair of genetic scissors guided by a GPS system.
Breaking Down the Name
| Term | What It Means |
|---|---|
| CRISPR | “Clustered Regularly Interspaced Short Palindromic Repeats” – part of bacterial DNA that fights viruses |
| Cas9 | An enzyme that acts like molecular scissors to cut DNA at specific sites |
How Does It Work?
- A guide RNA (gRNA) finds the exact DNA sequence to edit
- Cas9 enzyme cuts the DNA at the targeted location
- The cell repairs the DNA by:
- Disabling a gene
- Fixing a mutation
- Inserting a new gene
Example:
CRISPR can correct the faulty gene that causes sickle cell anemia. The repaired gene helps the body make healthy red blood cells.
Uses of CRISPR-Cas9
| Field | Application |
|---|---|
| Medicine | Cures for genetic diseases like cystic fibrosis and blindness |
| Agriculture | Drought-resistant and pest-resistant crops |
| Livestock | Healthier and faster-growing animals |
| Research | Turn genes on or off to study their functions |
Advantages
| Benefit | Why It Matters |
|---|---|
| Precise | Targets exact genes, avoiding random edits |
| Low cost | Cheaper than older gene-editing tools |
| Fast | Faster than traditional breeding or GM |
| Wide use | Works in bacteria, plants, animals, and humans |
Ethical Concerns & Risks
| Concern | Why It’s a Problem |
|---|---|
| Designer babies | Editing embryos for traits like IQ raises ethical issues |
| GMO backlash | Public concern about editing food genes |
| Off-target edits | Risk of cutting the wrong part of DNA |
| Unequal access | Technology may benefit only richer countries |
CRISPR vs Traditional GM
| Feature | Traditional GM | CRISPR-Cas9 |
|---|---|---|
| Speed | Slower | Much faster |
| Accuracy | Less targeted | Highly precise |
| Cost | Higher | Lower |
| Method | Often inserts foreign genes | Edits existing genes directly |
GMOs in Agriculture: Golden Rice & Bt Cotton
What Are GMOs?
GMOs (Genetically Modified Organisms) are plants or animals whose DNA has been altered using biotechnology. In agriculture, GMOs help create crops that:
- Grow faster
- Resist pests or drought
- Improve nutrition
- Reduce the need for harmful chemicals
GM crops are created by inserting specific genes into a plant’s DNA to give it new traits.
Case Study 1: Golden Rice
What is Golden Rice?
Golden Rice is a genetically modified variety of rice that produces beta-carotene, which the human body converts into Vitamin A. It was developed to help fight Vitamin A deficiency in countries where rice is a staple food.
Why Was It Needed?
- Vitamin A deficiency causes blindness and lowers immunity
- Common in poor regions of Asia and Africa
- Regular rice has no Vitamin A
How Was It Made?
Genes from a daffodil and a soil bacterium were added to rice DNA. This enables the rice to produce beta-carotene, which gives the rice a golden color and nutritional value.
| Advantage | Impact |
|---|---|
| Provides Vitamin A | Helps prevent blindness and child deaths |
| Can be grown like normal rice | Fits into existing farming systems |
| Low cost to poor families | Can be distributed freely to small farmers |
| Concern | Explanation |
|---|---|
| GM food safety | Long-term health effects are debated |
| Biodiversity | May affect traditional rice varieties |
| Public trust | Many people fear GMOs due to misinformation |
Case Study 2: Bt Cotton
What is Bt Cotton?
Bt cotton is genetically engineered to produce a toxin from the bacterium Bacillus thuringiensis (Bt), which kills common cotton pests like the bollworm.
Why Was It Needed?
- Pest attacks caused heavy crop losses
- Farmers used harmful and expensive pesticides
- Bt cotton reduced pesticide use and increased yield
How Was It Made?
A Bt gene was inserted into cotton DNA. The plant then makes a protein that is toxic to pests but safe for humans.
| Advantage | Impact |
|---|---|
| Kills major pests | Reduces crop damage and loss |
| Less pesticide use | Healthier for farmers and environment |
| Higher yields | Increased income for farmers |
| Widespread adoption | Used by millions of Indian farmers since 2002 |
| Concern | Explanation |
|---|---|
| Resistance in pests | Some pests evolve to survive Bt toxin |
| Higher water use | Bt cotton often needs more irrigation |
| Impact on non-target insects | May harm beneficial insects if not managed |
Transgenic Organisms
What Is a Transgenic Organism?
A transgenic organism is a plant, animal, or microbe that has been genetically modified by inserting DNA from a different species. This inserted gene provides a new, useful trait such as resistance to disease, faster growth, or the ability to make medicines.
How Are Transgenic Organisms Made?
- Select a useful gene from one organism (e.g., insulin-producing gene)
- Cut the gene using special enzymes
- Insert it into a vector (like a plasmid or virus)
- Transfer the vector into the target organism’s DNA
- Grow and reproduce the modified organism – it now shows the new trait
This process is part of genetic engineering or recombinant DNA technology.
Examples of Transgenic Organisms
| Organism | Added Gene From… | Purpose |
|---|---|---|
| Bacteria (E. coli) | Human gene for insulin | Produces insulin for diabetic patients |
| Bt Corn | Bacillus thuringiensis (Bt gene) | Makes plant resistant to pests |
| GM Cow | Human/engineered gene | Produces milk with extra proteins |
| Transgenic Mice | Human genes | Used in medical research |
Key Features
- Carry foreign genes in their genome
- Can pass new traits to offspring
- Used in agriculture, healthcare, and scientific research
- Tested for safety before use
Benefits of Transgenic Organisms
| Benefit | Explanation |
|---|---|
| Better crops | More resistant to pests, drought, or disease |
| Medical breakthroughs | Production of insulin, vaccines, and hormones |
| Scientific understanding | Helps study human diseases using model organisms |
| Environmental protection | Reduces pesticide use by making pest-resistant crops |
Concerns and Challenges
| Concern | Explanation |
|---|---|
| Ethical issues | Altering life raises moral questions |
| Environmental risks | GM traits could spread to wild species |
| Cross-contamination | Genes may transfer to non-GM crops |
| Farmer dependence | Small farmers may become reliant on patented seeds |