I/GCSE Biology Question Analysis Topic: Biology - Short Questions
Exam Questions:
1) All cloning vectors have a 'selectable marker'. Describe its role in recombinant DNA-technology.
2) Following a road accident four injured persons were brought to a nearby clinic. The doctor immediately injected them with tetanus antitoxin. What is tetanus antitoxin?
Answer:
For I/GCSE Biology, you should know:
1) Selectable markers play many roles when it comes to recombinant DNA technology. For example:
- Aid in the selection of host cells containing the vectors.
- The possibility of selecting non-transformants (as opposed to transformants) is eliminated with their help.
- For E.coli, selectable markers are genes that encode resistance to antibiotics.
2) A sterile, nonpyrogenic solution of refined and concentrated proteins, primarily globulins, including antitoxic antibodies is known as tetanus antitoxin. It is made from the blood serum or plasma of healthy horses that have had tetanus toxin vaccinations.
The toxins produced by Clostridium tetani would be instantly neutralized by tetanus antitoxin. Because Clostridium tetani could enter a patient's body through a bleeding wound after a highway accident, antitoxin is given to the patient instead of a tetanus shot.
Work hard for your I/GCSE Biology examination!
End of analysis. Great!