Quiz On Gene Therapy (Ch-20)

Restriction enzymes are proteins that cut DNA molecules at specific locations. They recognize specific DNA sequences and cleave the DNA at those sites. This process is important in genetic engineering and molecular biology techniques, as it allows scientists to manipulate and study specific DNA fragments. Gene cloning involves the insertion of DNA fragments into vectors, DNA ligase is an enzyme that joins DNA fragments together, gel electrophoresis is a technique used to separate DNA fragments based on their size, and reverse transcriptase is an enzyme used to generate complementary DNA from RNA templates.

Gel electrophoresis separates molecules based on their size and electrical charge. In this technique, a mixture of molecules is loaded onto a gel matrix, and an electric current is applied. The negatively charged molecules move towards the positive electrode, with smaller molecules moving faster than larger ones. As a result, the molecules separate into distinct bands based on their size. The gel matrix acts as a sieve, allowing smaller molecules to pass through more easily. The separation of molecules in gel electrophoresis is essential for various applications, such as DNA analysis, protein characterization, and genetic engineering.

Gene cloning is the correct answer because it is the process of producing multiple identical copies of a gene. This technique is used in basic research to study the function of genes and in large-scale production of gene products, such as proteins. Gene cloning involves isolating a specific gene of interest, inserting it into a vector (such as a plasmid), and then replicating the gene within a host organism, such as bacteria. This allows for the production of a large quantity of the gene or gene product for further analysis or use.

DNA ligase is the correct answer because it is an enzyme that seals or joins together the sticky ends of restriction fragments during the process of recombinant DNA technology. Restriction enzymes are responsible for cutting DNA at specific sequences, gene cloning involves the insertion of DNA fragments into a vector, gel electrophoresis is used to separate DNA fragments based on size, and reverse transcriptase is an enzyme used in the synthesis of cDNA from RNA.

Reverse transcriptase is used to make complementary DNA (cDNA) from RNA. Reverse transcriptase is an enzyme that can synthesize DNA using an RNA template. It catalyzes the reverse transcription process, where RNA is used as a template to produce complementary DNA strands. This enzyme is commonly used in molecular biology research to convert RNA molecules into DNA, allowing for further analysis and manipulation of the genetic material.

Southern blotting is a technique developed by a British researcher that involves transferring DNA sequences onto a membrane and identifying them using a probe. This technique is specifically used to detect and analyze specific DNA sequences, such as gene expression or DNA methylation patterns. It is named after the scientist Edwin Southern, who first described the method in 1975.

RT-PCR, or Reverse Transcription Polymerase Chain Reaction, is a molecular biology technique that uses reverse transcriptase to convert RNA into complementary DNA (cDNA), followed by amplification of the cDNA. This technique is commonly used to study gene expression and detect RNA viruses. In RT-PCR, reverse transcriptase synthesizes a strand of cDNA from the RNA template, and then DNA polymerase amplifies the cDNA through multiple cycles of denaturation, annealing, and extension. This process allows for the detection and quantification of specific RNA molecules in a sample.

One of the technical reasons why gene therapy is problematic is that transferred genes may not have appropriately controlled activity. This means that the genes that are introduced into cells may not be regulated properly, leading to potential overexpression or underexpression of the gene product. This lack of control can have negative consequences and may not achieve the desired therapeutic effect.

Transgenic plants are genetically modified plants that can produce human proteins, including vaccines. However, one possible hindrance that must be overcome is the prevention of transmission of plant allergens to the vaccine recipients. This means that measures must be taken to ensure that the vaccines produced by the transgenic plants do not contain any allergenic substances that could cause allergic reactions in the recipients.

Western blotting is a technique used to transfer and analyze polypeptide sequences on a membrane. It involves the separation of proteins using gel electrophoresis, followed by transfer onto a membrane and detection using specific antibodies. This technique is commonly used to study gene expression by identifying the presence and quantity of specific proteins in a sample. Southern blotting is used for DNA analysis, Northern blotting is used for RNA analysis, Eastern blotting is not a recognized technique, and RT-PCR is a method for amplifying and detecting RNA.

RFLP analysis, or Restriction Fragment Length Polymorphism analysis, is a technique used to detect variations in DNA sequences. It involves the use of restriction enzymes to cut DNA at specific recognition sites. These recognition sites can vary between alleles, resulting in different fragment lengths when the DNA is cut. By comparing the fragment lengths produced by the restriction enzymes, we can distinguish between different alleles. Therefore, the correct answer is "restriction enzyme recognition sites between the alleles."