What is a prion?

Question

What is a prion?

BlackTom AI · Accepted Answer

Exploring what a prion is requires distinguishing it from other infectious agents mentioned in the options.
Option 1: 'A class of viruses that travels up peripheral nerves to attack the brain' This describes a viral mechanism, but prions are not viruses; they are misfolded proteins that propagate by inducing misfolding in normal proteins, not by viral infection.
Option 2: 'A class of bacteria that can cause meningitis' Prions are not bacteria, and they are not cells at all. Bacteria are cellular organisms, whereas prions are simply proteins, so this option misclassifies prions entirely.
Option 3: 'A class of viruses that can cause encephalitis' Again, this attributes a viral etiology to prions. Prions lack nucleic acids and do not replicate like viruses; this statement incorrectly assigns a viral nature to prions and also references a disease outcome (encephalitis) that is not the defining feature of prions.
Option 4: 'A class of proteins capable of infecting brain tissue' This is the accurate characterization: prions are misfolded protein forms that can induce misfolding in normal brain proteins, leading to neurodegenerative disease. They are not viruses, bacteria, or cells, and they act through protein-only mechanisms affecting brain tissue.
Option 5: 'None of the above describes a prion' This would be incorrect because Option 4 already provides an accurate description of prions, making this statement false.
In summary, the key distinctions are that prions are not viruses or bacteria and do not rely on nucleic acids for propagation; they are abnormal proteins that propagate by altering normal proteins, particularly affecting brain tissue. This aligns precisely with Option 4, leaving the other options based on common misconceptions about infectious agents in brain diseases.

What is a prion?单项选择题

类似问题

Question at position 1 Learning Objective 1 Prions are a biological contaminant that can cause foodborne illness.TrueFalse

Prions are best described as:

Which of the following is NOT true concerning prions?

True or False: Treatment with proteases destroyed the causative agent causing Scrapie.

What is a prion?

Which etiologic agent causes Mad Cow Disease?

Which of the following trees corresponds to a potential parse of the ambiguous sentence below, with correct syntactic categories? Some diagnostics are provided.

Which of the following sentences contain two non-finite verbs? Select all that apply.

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单