Answer :
8.3.1 Define Genetic Engineering
Genetic engineering is the process of altering the genetic material of organisms to change its traits or characteristics. This is done by manipulating the DNA to either insert, delete, or modify specific genes. The goal is to introduce desirable traits or eliminate undesirable ones. It has applications in various fields such as medicine, agriculture, and biotechnology.
8.2.2 Describe the Steps Involved in Producing Recombinant DNA
Isolation of the Gene of Interest: The first step is to identify and isolate the gene that needs to be inserted into the host organism. This can be done using restriction enzymes which cut DNA at specific sequences.
Insertion into a Vector: The isolated gene is then inserted into a DNA vector, often a plasmid, which acts as a vehicle to transfer the gene into the host cell. The vector is also cut using the same restriction enzymes to ensure the gene can be spliced into it seamlessly.
Transformation: The recombinant DNA is introduced into host cells, such as bacteria, through a process called transformation. This involves preparing the host cells and encouraging them to take up the plasmid DNA.
Selection and Screening: The bacteria that have successfully taken up the recombinant plasmid are selected using markers (often antibiotic resistance genes). These colonies are then grown in culture for further use.
Expression of the Gene: The host cells express the new gene, producing the desired protein or trait, which can then be harvested and used for various applications.
8.3.3 Explain Why Bacteria Are Most Suitable for Genetic Engineering
Rapid Growth and Division: Bacteria can reproduce quickly, producing many copies of the desired recombinant DNA in a short amount of time.
Simple Genome and Easy Manipulation: Bacteria have relatively simple genetic structures compared to eukaryotes, making them easier to manipulate genetically.
Well-Established Techniques: Scientists have developed a wide range of tools and methods specifically for transforming and manipulating bacterial DNA, making it a standard practice in laboratories.
8.3.4 Suggest Three Objections That Some People Might Have to Genetic Engineering
Ethical Concerns: Some people believe that altering the genetic makeup of organisms is unnatural and raises ethical questions about the extent of human intervention in nature.
Safety Concerns: There are fears about the potential unintended consequences of releasing genetically modified organisms (GMOs) into the environment, such as the creation of new allergens or the transfer of genes to non-target species.
Economic and Social Issues: There is concern that genetic engineering can lead to increased corporate control over food sources, restricted access for small farmers, and a widening gap between rich and poor countries in terms of food and technology accessibility.
