Biology 1001A Lecture Notes - Lecture 2: Natural Selection, Thymidine, Smallpox
25 Apr 2017
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Bio 1001a- lecture 2- hiv evolution sept. 15/ 2016. Outcomes: characteristics of viruses and why they are not generally considered to be (cid:498)alive(cid:499). Not the same cell structure: why viral infections are usually difficult to treat with drugs, and exceptions to this general principle. Viruses that use their own polymerases (eg. rna viruses such as. influenza) are easier to target and treat w antivirals: whether viruses are always pathogenic. Not all viruses are pathogenic as many benefit their hosts and actually protect against pathogens eg. bacteriophages which prevent too much bacteria growth: hypotheses for the evolutionary origin of viruses. Hypothesis a: -may have evolved from fragments of rna/ dna. Evolved after cells appeared (since they rely on cells) First fragments become surrounded by protein with recognition. Hypothesis b: - viruses thought to be ancient, predating cells: lifecycle of hiv. Virion hooks onto receptors and enters host cell.
