Topic 19: Genetic Technology Flashcards
Definitions I:
(a) Recombinant DNA
(b) Genetic engineering
(c) Gene therapy
(a) Recombinant DNA: DNA combined from different sources. (1 mark)
(b) Genetic engineering: Altering DNA to change traits. (1 mark)
(c) Gene therapy: Treating disease with genes. (1 mark)
In a bacterium, explain what recombinant DNA is. [2 Marks]
DNA from two organisms joined (1 mark); Forms new genetic combo in bacterium (1 mark). (2 marks)
In a lab, explain how a gene is transferred into a plant to express herbicide resistance. [3 Marks]
Gene inserted via plasmid (1 mark); Restriction enzymes cut, ligase joins (1 mark); Plant expresses resistance (1 mark). (3 marks)
Describe three ways to obtain a gene for transfer into a mouse. [3 Marks]
Extracted from donor DNA (1 mark); Synthesised from mRNA via reverse transcriptase (1 mark); Chemically built from nucleotides (1 mark). (3 marks)
In E. coli, explain the roles of restriction endonucleases and DNA ligase in gene transfer. [2 Marks]
Endonucleases cut DNA at sites (1 mark); Ligase joins gene to plasmid (1 mark). (2 marks)
Explain why a promoter is needed when transferring a gene into a yeast cell. [2 Marks]
Promoter initiates gene transcription (1 mark); Ensures expression in yeast (1 mark). (2 marks)
In a tomato plant, explain how marker genes confirm gene expression. [2 Marks]
Marker genes glow fluorescent (1 mark); Show successful gene uptake (1 mark). (2 marks)
In a human cell, describe how gene editing modifies the genome. [3 Marks]
CRISPR targets specific DNA (1 mark); Inserts, deletes, or replaces bases (1 mark); Alters genome function (1 mark). (3 marks)
In a forensic lab, explain the steps of PCR to amplify DNA. [4 Marks]
Denature DNA at 95°C (1 mark); Anneal primers at 55°C (1 mark); Taq polymerase extends at 72°C (1 mark); Amplifies DNA (1 mark). (4 marks)
Describe how gel electrophoresis separates DNA in a paternity test. [3 Marks]
DNA fragments move in gel (1 mark); Smaller go farther, electric field (1 mark); Bands show lengths (1 mark). (3 marks)
Explain the advantages of recombinant insulin for diabetes treatment. [3 Marks]
Recombinant insulin pure, human-like (1 mark); No allergies, mass-produced (1 mark); Controls diabetes effectively (1 mark). (3 marks)
In a cancer study, outline how microarrays detect gene expression. [2 Marks]
Microarrays hybridise mRNA to probes (1 mark); Fluorescence shows expressed genes (1 mark). (2 marks)
In a family, outline the advantages of genetic screening for cystic fibrosis. [3 Marks]
Screening detects CFTR mutations (1 mark); Early treatment, planning (1 mark); Reduces disease impact (1 mark). (3 marks)
In agriculture, explain how GM salmon and herbicide-resistant soybean improve food supply. [4 Marks]
GM salmon grow faster (1 mark); Soybean resists herbicides, higher yield (1 mark); Both boost food (1 mark); Ethical concerns debated (1 mark). (4 marks)
Discuss social and ethical issues of gene therapy for SCID in a child. [4 Marks]
Gene therapy fixes SCID immunity (1 mark); High cost, access issues (1 mark); Risk of errors (1 mark); Ethics of consent (1 mark). (4 marks)
