Biotechnology: tools and techniques Flashcards
What is biotechnology?
The use of biological systems, organisms, or their components to develop new technologies, improve health, and enhance industry.
What are the main areas of biotechnology?
- Genetic Engineering – Modifying DNA for beneficial traits.
- Medical Biotechnology – Producing medicines, gene therapy.
- Agricultural Biotechnology – Improving crops & livestock.
- Industrial Biotechnology – Producing biofuels, biodegradable plastics.
What is recombinant DNA technology?
A process where DNA from different sources is combined to create new genetic sequences.
What are the key steps in recombinant DNA technology?
- Extract DNA from donor cells.
- Cut DNA using restriction enzymes.
- Insert DNA into a plasmid (vector).
- Transform bacteria with recombinant plasmid.
- Allow bacteria to multiply and express the gene.
How is DNA extracted from cells?
- Obtain a cell sample (e.g., cheek swab, blood).
- Break open the cells using detergents.
- Separate DNA using centrifugation.
- Isolate DNA from proteins & other cell components.
What are gene probes?
Short, single-stranded DNA or RNA sequences labeled with radioactive or fluorescent markers to locate specific genes.
How are gene probes used?
They bind to a complementary sequence in the DNA, allowing scientists to detect specific genes.
What are restriction enzymes?
Enzymes that cut DNA at specific sequences, creating sticky or blunt ends.
What is an example of a restriction enzyme?
EcoR1 – Recognizes GAATTC and cuts between G and A.
What is PCR? (Polymerase Chain Reaction)
A technique used to amplify (copy) small amounts of DNA.
What are the three steps of PCR?
- Denaturation (95°C) – DNA strands separate.
- Annealing (50-65°C) – Primers bind to target DNA.
- Extension (72°C) – DNA polymerase builds new strands.
What enzyme is used in PCR?
Taq DNA polymerase – It withstands high temperatures.
What is gel electrophoresis?
A method to separate DNA fragments based on size using an electric field.
How does DNA move in gel electrophoresis?
• Negatively charged DNA moves toward the positive electrode.
• Smaller fragments move faster and travel further.
What is transgenesis?
The transfer of a gene from one species to another to create a transgenic organism.
What are the common methods for gene transfer?
• Microinjection – Direct injection into the nucleus.
• Viral Vectors – Modified viruses carry the gene.
• Electroporation – Electric shock opens cell membranes.
• Agrobacterium-mediated transfer – Used for plants.
What is CRISPR-Cas9?
A revolutionary gene-editing tool that allows scientists to precisely cut, remove, or replace DNA sequences.
What does “CRISPR” stand for?
Clustered Regularly Interspaced Short Palindromic Repeats—a defense system found in bacteria against viruses.
What are the two main components of CRISPR?
Guide RNA (gRNA) – Directs Cas9 to the specific DNA sequence.
Cas9 Enzyme – Acts as molecular scissors to cut the DNA.
How does CRISPR work?
- gRNA binds to the target DNA sequence.
- Cas9 enzyme cuts the DNA at the specific location.
- The cell repairs the cut, allowing scientists to insert, delete, or modify genes.
What are two DNA repair pathways after a CRISPR cut?
Non-Homologous End Joining (NHEJ) – Creates small mutations, often used to disable genes.
Homology-Directed Repair (HDR) – Allows precise gene insertion using a template.
Applications of CRISPR
Curing genetic diseases (e.g., sickle cell anemia, cystic fibrosis)
Creating disease-resistant crops
Eliminating viruses (e.g., HIV, herpes)
Growing organs for transplantation
What are the three types of cloning?
Gene Cloning – Copying specific genes.
Reproductive Cloning – Creating a genetically identical organism (e.g., Dolly the sheep).
Therapeutic Cloning – Creating embryonic stem cells for medical treatment.
What are common applications of recombinant DNA?
Producing human insulin
Creating vaccines (e.g., hepatitis B, HPV)
Developing genetically modified crops
What is gene therapy?
A technique that replaces, removes, or repairs faulty genes to treat genetic disorders.
What are the two types of gene therapy?
Somatic Gene Therapy – Alters genes in body cells (not inheritable).
Germline Gene Therapy – Alters genes in sperm/egg cells (inheritable, but controversial).
What are two main delivery methods for gene therapy?
Viral Vectors – Modified viruses insert genes into human cells.
Non-Viral Methods – Direct injection of DNA or CRISPR-based editing.
Examples of Gene Therapy in Medicine
SCID (“Bubble Boy Syndrome”) – Repaired using gene therapy.
Leber’s Congenital Amaurosis (LCA) – Restores vision in blind patients.
CAR-T Cell Therapy – A form of gene therapy that programs immune cells to fight cancer.
What are genetically modified organisms (GMOs)?
Organisms whose DNA has been altered to introduce beneficial traits.
Examples of GMO Crops
🌾 Golden Rice – Contains vitamin A to prevent blindness.
🌽 Bt Corn – Produces an insecticidal protein.
☘️ Roundup Ready Crops – Herbicide-resistant soybeans & corn.
🍅 Flavr Savr Tomato – Longer shelf life.
Pros & Cons of GMOs
✅ Advantages
• Increased crop yield
• Pest resistance (less pesticide use)
• Drought resistance
• Added nutrition (e.g., Golden Rice)
❌ Disadvantages
• Crossbreeding with wild species
• Potential unknown health effects
• Ethical concerns over “patenting life”
What is DNA sequencing?
Determining the exact order of nucleotides (A, T, C, G) in DNA.
What are the steps in DNA sequencing?
PCR amplifies DNA.
Fluorescently labeled nucleotides terminate DNA strands.
Capillary electrophoresis separates DNA fragments.
Laser detection determines the sequence.
Forensic Applications
Crime Scene Investigation – DNA left at a crime scene can identify suspects.
Paternity Testing – STR (Short Tandem Repeat) analysis determines biological relationships.
Identifying Remains – DNA can confirm identities in disasters.
How does DNA profiling work?
DNA is extracted from evidence (blood, hair, saliva).
PCR amplifies STR regions of DNA.
Electrophoresis separates DNA fragments.
A DNA profile is compared to suspects’ DNA.
What are ethical concerns with biotechnology?
• Health Risks – Potential for allergic reactions or unknown side effects.
• Environmental Risks – GMOs may crossbreed with wild species.
• Economic Issues – Large biotech companies control patents on seeds.
• Religious & Cultural Concerns – Modifying life may conflict with beliefs.
What are emerging fields in biotechnology?
• Synthetic Biology – Designing new biological parts & systems.
• Gene Therapy – Editing human genes to cure genetic disorders.
• 3D Bioprinting – Printing organs and tissues.
• Personalized Medicine – Using genetic information to tailor treatments.
What is the key that unlocks the doors of knowledge?
“Study while others are sleeping; work while others are loafing; prepare while others are playing; and dream while others are wishing” - William Arthur Ward.
