What is the definition of biotechnology?
The technology and process of using biology, biological systems, or processes to produce products or provide services.
What are examples of biotechnology?
Traditional (past): Making cheese, brewing, breeding, etc.
Modern: Manipulating DNA, cells, tissues, or biological processes to gain knowledge, produce products, or provide services.
What is the relationship between genetic engineering and cloning with biotechnology?
Genetic engineering and cloning are examples of modern biotechnology.
What is recombinant DNA technology?
A technology that inserts new genes into the DNA of organisms.
Explain the principle of recombinant DNA technology (using the production of human insulin as an example).
(1) Obtain the target gene (the DNA fragment encoding human insulin).
(2) Obtain the plasmid from bacteria as a vector.
(3) Use the same restriction enzyme (restriction endonuclease) to cut the DNA fragment and the plasmid.
(4) Use DNA ligase to join the DNA fragment and the plasmid together to form a recombinant plasmid.
(5) Introduce the recombinant plasmid into the host cell, which will replicate and express the gene. This is called transformation.
What is a restriction enzyme? What is its working principle?
A protein that can recognize a specific short nucleotide sequence (restriction site) in double-stranded DNA and cut both strands of the DNA molecule.
Note: It may produce blunt ends or sticky ends depending on the type of restriction enzyme.
How can host cells with recombinant DNA be screened?
Use plasmids with selective markers (e.g., antibiotic resistance genes) as vectors.
Place the transformed host cells (including the marker gene and target gene) into the relevant antibiotic for cultivation.
The host cells with resistance will survive and can thus be selected.
What are the benefits of using recombinant DNA technology? (Using the production of human insulin as an example)
(1) Fast production
(2) Lower cost
(3) Higher yield
(4) Produced human insulin is not rejected by the immune system (due to higher purity).
(5) Lower risk of other infections (due to higher purity).
What is a genetically modified organism?
An organism whose genetic composition has been altered through genetic engineering.
How to produce genetically modified bacteria using bacteriophages?
(1) Insert a new gene into the bacteriophage DNA.
(2) The bacteriophage will naturally infect the relevant bacteria.
(3) The bacteriophage will inject the recombinant DNA (including the new gene and viral DNA) into the bacteria.
(4) The target gene will integrate into the bacterial chromosome.
How to produce genetically modified plants using Agrobacterium or gene guns?
Agrobacterium is a bacterium that can infect plants.
(1) Create transformed Agrobacterium.
(2) Use the transformed Agrobacterium to infect plant cells.
(3) The new gene will transfer into the plant cell's DNA.
(4) Cultivate the infected plant cells into new plants.
Gene gun is a tool that can inject DNA into cells.
(1) Directly inject DNA into plant cells.
(2) The DNA wrapped in metal powder will diffuse out.
(3) It may randomly integrate into the plant's chromosomes.
How to produce genetically modified animals? (Using microinjection, viruses, or liposomes)
Microinjection: Use an extremely fine needle to inject the DNA of the new gene directly into the fertilized egg.
Viruses: Infect the animal with a virus containing recombinant DNA.
Liposomes: Package the new gene into lipid vesicles, which fuse with the animal cell membrane to deliver the DNA of the new gene.
What are the benefits of producing genetically modified organisms?
(1) Low cost
(2) Fast production
(3) High yield
(4) Reduced agricultural pollution
What are the potential risks of producing genetically modified organisms?
(1) Long-term effects on human health
(2) Potential allergic reactions
(3) Risk of creating superbugs
(4) Risk of genetic pollution
(5) Potential disruption of natural ecosystems, reducing biodiversity
(6) Impact on species' gene pools with unknown long-term consequences
Explain the principle of plant tissue cloning (cloning) technology.
Cloning is the process of producing genetically identical individuals, i.e., replicating organisms.
Asexual reproduction is a natural form of cloning.
Principle:
(1) Plant cells easily grow and develop into complete plants.
(2) Extract part of the plant's meristem tissue for tissue culture (micropropagation).
Explain the benefits and limitations of tissue culture in cloning plants.
Benefits:
A large number of plants can be produced in a short time.
Limitations:
The process is complex, requires highly skilled personnel, and is costly.
Explain the two main technical principles of animal cloning.
(1) Embryo splitting
When a fertilized egg divides into multiple cells, the cells are still undifferentiated.
Extract the undifferentiated cells.
Each cell can continue dividing and develop into a new individual.
Note: This mimics the natural process of monozygotic twinning.
(2) Nuclear transfer
Remove the nucleus from the egg.
Transfer the nucleus of a somatic cell into the egg.
The egg with the transferred nucleus will continue to develop.
Explain the applications and limitations of animal cloning.
Applications:
(1) Breeding livestock
(2) Breeding endangered animals
(3) Mass-producing genetically modified animals
(4) Producing genetically identical animals for drug testing or other research
(5) Obtaining stem cells for research
Limitations:
(1) Low success rate
(2) Shorter lifespan of cloned animals
Explain the advantages and disadvantages of cloning.
Discuss the issues related to plant and animal cloning, including ethical, economic, and environmental concerns.
Discuss the issues related to human cloning.
What is polymerase chain reaction (PCR)?
Polymerase chain reaction (PCR) is a method for rapidly producing DNA copies outside of cells.
What materials are needed for PCR?
(1) DNA sample (containing the DNA segment to be amplified, i.e., the target region)
(2) Free nucleotides (deoxyribonucleotide triphosphates, dNTPs)
(3) Heat-resistant DNA polymerase
(4) Two primers, short synthetic single-stranded DNA sequences marking the start and end points
Explain the principle of PCR.
(1) DNA denaturation (requires high temperature)
(2) Primer annealing
(3) Extension to form a new DNA strand
(4) Repeat the above process
Describe the technical process of performing PCR.
List some applications of PCR.
(1) Diagnosing genetic diseases
(2) Forensic science
(3) Research on extinct organisms
(4) Diagnosing infectious diseases
(5) Identifying genetically modified food
What is DNA fingerprinting?
A technique that analyzes DNA fragments of different lengths to distinguish between individuals.
Explain the principle of DNA fingerprinting.
(1) Part of an individual's DNA sequence contains genetic variations (about 0.1%).
(2) Some genetic variations appear as variable number tandem repeats (VNTRs).
(3) The number of sequence repeats varies greatly between individuals, and the length of VNTRs also differs.
(4) By analyzing the different lengths of VNTRs (DNA fragments), individuals can be distinguished.
Important note: DNA sequences are not analyzed; only VNTR lengths are compared.
List the applications of DNA fingerprinting.
(1) Forensic science
(2) Paternity testing
(3) Identifying disaster victims
(4) Authentication of food and traditional Chinese medicine
(5) Conservation of endangered species
(6) Tracing the source of infectious diseases
(7) Screening for genetic diseases