Applications in biotechnology: Practice Questions

Which of the following pharmaceutical products is specifically produced through the fusion of B-lymphocytes and cancer cells to create hybridomas?

The production of human insulin using genetically modified bacteria is a significant achievement in biotechnology. What is the primary advantage of this method over obtaining insulin from animal sources (e.g., pigs or cattle)?

In the process of producing human insulin using recombinant DNA technology, scientists often synthesize the gene from mRNA using reverse transcriptase rather than isolating it directly from human genomic DNA. What is the primary biological rationale for this approach when using a bacterial host like Escherichia coli?

Which of the following biotechnological applications primarily involves the modification of an organism's genetic material to introduce a new trait or function?

Consider the ethical implications surrounding the use of genetically modified (GM) crops. Which of the following represents the MOST significant ecological concern regarding the widespread cultivation of herbicide-resistant GM crops?

State the main function of genetically modified bacteria in the production of human insulin.

Explain why a cDNA library, rather than a genomic DNA library, is preferred when the objective is to express human proteins in bacterial cells.

In gene therapy, viral vectors are commonly used to deliver genes into human cells. Explain why the use of viral vectors might trigger a host immune response and how this could affect the effectiveness of the treatment. (4 marks)

Animal cloning, particularly the method used to create Dolly the sheep, represents a significant milestone in biotechnology. This process relies on specialized techniques to manipulate cellular material.

(a) Outline the major steps involved in the somatic cell nuclear transfer (SCNT) process used to clone a mammal. (3 marks)

(b) Distinguish between reproductive cloning and therapeutic cloning in terms of their primary objectives. (2 marks)

DNA profiling is extensively used in forensic science and wildlife conservation to identify individuals or determine the source of biological materials. Imagine a scenario where a fragment of skin is found at a crime scene involving an endangered species.

(a) The Polymerase Chain Reaction (PCR) is first employed to amplify specific DNA regions. Explain why the temperature is lowered to approximately \(55^\circ\text{C}\) during the second stage of each PCR cycle and how the specificity of this process is achieved. (2 marks)

(b) Following PCR, gel electrophoresis is conducted. Explain how the properties of the DNA molecule and the gel matrix interact to allow the separation of DNA fragments of different lengths. (2 marks)

(c) In a legal case, a prosecutor must prove that the skin fragment belongs to a specific animal. Explain the statistical advantage of analyzing ten different Short Tandem Repeat (STR) loci compared to analyzing only two. (2 marks)

(d) Some argue that genetic information of individuals, including endangered species, should be patentable. State one social or ethical implication of allowing the patenting of naturally occurring genetic sequences. (1 mark)