BIOL 1202 : Bio Exam 3 Starts Here
Document Summary
Viroids-even simpler and smaller than viruses: only has a genome. No capsid like the virus; fragments of single stranded rna with no protein coat; hijack cells; infects primarily plant cells including citrus trees, potatoes, avocados (the journal of science/nature) Prion(simply a polypeptide/sequence of amino acids/a sticky blob of amino acids/ protein particle with no genetic material(ie. dna or rna) clumps bind with protein production and over time can lead to brain tissue damage- i. e. mad cow or. Creutzfeldt-jakob disease and kuru(tribe of people who practice cannibalism/they ate brains); prions consist of a protein that is folded wrong and makes other proteins fold wrong; origin: developed as a by-product of living organisms. 14000 species described, may be 100-1000x that number. 1st organisms to appear on earth, 3. 5 billion years age. Cell wall: semi-rigid, permeable, made of peptidoglycan (carbohydrate with amino acids attached). Gives bacteria shapes; 2 main types-thick and thin(thick stain positive-gram positive cell; thin- negative)
