Question

Infectious proteins are present in
(a) Satellite viruses
(b) Gemini viruses
(c) Prions
(d) Viroids

Answer 1

It's a kind of protein that will trigger normal proteins within the brain to fold abnormally. They are so small and are not living organisms. They do not contain nucleic acid, unlike other pathogens.

Complete answer:
Infectious proteins are present in prions. They are the infectious agents responsible for several neurodegenerative diseases in mammals, like Creutzfeldt Jakob disease. This happens due to the abnormal folding of the proteins in the brain.
The main reason behind prion diseases is the abnormal folding and clumping of prions within the brain causing brain damage. This leads to memory impairment, changes in personality, and difficulties in moving. Prions are by far the most dangerous infections caused by the agents already present within the body and are usually fatal. However, a lot has not been discovered about prion diseases.
The protein that prions are made from is PrP, which is found throughout the body, even in healthy people and animals. However, PrP found in infectious material features a different structure and is resistant to proteases. Proteases are the enzymes in the body that can normally break down proteins. The physiological function of the prion protein remains poorly understood.
The symptoms of Prion diseases are:
- Confusion - Difficulty in speaking
- Developing dementia - Hallucinations - Fatigue - Stiffening of muscles
So, the correct answer is ‘Prions.’

Note:
- Prions form abnormal aggregates of proteins called amyloids, which accumulate in infected tissue and are associated with tissue damage and cell death.
- Discovering the mechanism of replication of prions has been a very difficult task. To find out how a protein can multiply with none cellular machinery was next to impossible.
- There are many other concepts related to prions that are unclear. Research is being carried out to figure out the prions for detailed studies.