Monday 24 April 2017

TRUE regarding prions | NEET Based MCQ


Which of the following is TRUE regarding prions? 

A. It contains nuclear material 
B. They are infectitious proteins 
C. Immunogenic 
D. DNA particle

Ans. B. (They are infectitious proteins)
Explanation
• Prions are proteinaceous infectious particles without any detectable nucleic acids, resistant to heat, UV rays and nucleas. and sensitive to proteases. They have the ability to convert the normal non-infectious form of protein in question in::
infectious prion form.
• Prion conversion is accompanied by a change in functional status of protein that allows a cell or organism to be in tso - ferent phenotypic states in which it respectively harbors the normal or the prion form of the particle.
• Prions are responsible for several fatal neurodegenerative disorders known as transmissible spongiform encephalopathies or prion diseases. In these conditions secondary or tertiary structure of a protein is altered.
• They are causative agents of[MCQ]
a. Kuru and Creutzfeldt-Jacob disease


b. Scrapie and Bovine spongiform encephalopathy (mad cow disease)