Biotechnology – JSS3 Intermediate Science Lesson Note (Second Term)

Biotechnology is the use of living organisms, such as bacteria, yeast or plant cells, or their biological processes to make useful products.

Behavioural objectives

By the end of the lesson, students should be able to:

1. Define biotechnology and give two everyday examples.
2. Distinguish between traditional and modern biotechnology.
3. State uses of biotechnology in agriculture, medicine and industry.
4. Outline how bacteria are used to make human insulin.
5. State one advantage and one concern about biotechnology.

What is biotechnology?

Biotechnology is the use of living organisms or their parts to make products that improve human life.

• Living organisms used: bacteria, yeast, fungi, plant cells and animal cells.
• Biological processes used: fermentation, enzyme action and the transfer of genes.
• Products made: medicines, better food, fuels and cleaning materials.
• Simple idea: scientists use the “tools” already found in microbes and plants to do useful work.

What are the types of biotechnology?

There are two types of biotechnology: traditional biotechnology and modern biotechnology.

Traditional biotechnology

• Meaning: use of microbes in food making, practised for thousands of years without knowing how they work.
• Bread: yeast makes dough rise.
• Yoghurt: bacteria turn milk sour and thick.
• Nigerian foods: ogi, garri, iru (fermented locust beans) and palm wine are made by fermentation.

Modern biotechnology

• Meaning: use of scientific methods, such as genetic engineering, to change the genes of organisms.
• Genetic engineering: moving a useful gene from one organism into another.
• Tissue culture: growing whole plants from small pieces of plant tissue in a laboratory.
• Examples: human insulin from bacteria and pest-resistant crops.

Traditional and modern biotechnology compared

What are the areas of biotechnology?

Biotechnology is used mainly in agriculture, medicine and industry.

How is biotechnology used in agriculture?

In agriculture, biotechnology is used to produce stronger crops and more food from the same land.

• Genetically modified (GM) crops: the plant’s DNA, its “instruction manual”, is changed to make it stronger, for example maize that resists pests and needs fewer chemical sprays.
• Improved yields: seeds that grow faster or give more food on a small piece of land.
• Drought resistance: crops that survive when rainfall is low, which helps farmers in dry areas.
• Food fortification: extra nutrients are added to a crop as it grows. Golden Rice has extra Vitamin A, which helps prevent blindness in children.
• Tissue culture: many identical, disease-free young plants are grown quickly from small plant pieces.

How is biotechnology used in medicine?

In medicine, biotechnology is used to prevent, treat and sometimes cure diseases.

• Vaccines: safe forms of germs “train” the immune system. Vaccines against polio, measles and COVID-19 are examples.
• Insulin: insulin once came from animals. Bacteria with a human insulin gene now make human insulin in large tanks.
• Gene therapy: a faulty gene is replaced with a working one. Research is going on for diseases such as sickle cell anaemia.
• Antibiotics: many antibiotics are made by fungi or bacteria. Penicillin comes from the fungus Penicillium.

How are bacteria used to make human insulin?

1. Scientists cut out the human gene that makes insulin.
2. The gene is placed inside a small ring of DNA from a bacterium.
3. The bacterium takes in the changed DNA.
4. The bacteria are grown in large tanks and multiply quickly.
5. The bacteria make insulin, which is collected and purified for patients.

How is biotechnology used in industry?

In industry, biotechnology is used to make fuels and cleaning products and to treat waste.

• Biofuels: petrol is non-renewable, but plants such as sugarcane and cassava can be fermented to make ethanol, which is used as fuel.
• Enzymes in detergents: enzymes made by microbes break down grease and stains, even in cold water.
• Waste treatment: bacteria in sewage plants break down waste in dirty water before it returns to rivers.

Is biotechnology safe?

Biotechnology has many benefits, but some people have concerns about its long-term effects.

Advantages

• Less chemical use: pest-resistant crops reduce the need for poisonous sprays.
• More food: higher yields help feed a growing population.
• Better health: more medicines and vaccines are available.
• Cleaner environment: biofuels and waste treatment reduce pollution.

Concerns

• Long-term effects: the effects of some GM foods on health and the environment are still being studied.
• Effect on natural plants: modified plants might crowd out natural ones.
• Cost: small farmers may find GM seeds expensive.

Who looks after biotechnology in Nigeria?

• NABDA: the National Biotechnology Development Agency promotes and develops biotechnology in Nigeria.
• NBMA: the National Biosafety Management Agency regulates modern biotechnology to make sure it is safe.

Evaluation

1. Define biotechnology in one sentence.
2. Name two traditional biotechnology foods made in Nigeria.
3. State two ways biotechnology helps a farmer.
4. Why is Golden Rice better than ordinary rice for a growing child?
5. List the steps used to make human insulin with bacteria.

Assignment

Write a short note on how biotechnology is used in agriculture, medicine and industry. Give two examples for each area and state one concern about GM foods.