A bacterium's genetic resistance to multiple antibiotics is transferred in vivo between cells via_____________?
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Answer: A. Conjugation
Explanation
Conjugation allows living bacteria to transfer genetic resistance plasmids directly through physical cell-to-cell contact. In vivo gene transfer spreads multidrug resistance rapidly among diverse bacterial populations inhabiting host tissues. Sex pili bridge donor and recipient cells to facilitate the physical passage of mobile genetic elements. Bacterial conjugation is a primary mechanism of horizontal gene transfer in natural microbial communities. Plasmids transferred during this process frequently carry genes encoding resistance to multiple antibiotic classes. This genetic exchange occurs independently of normal bacterial cell division and vertical inheritance.
The rapid spread of antibiotic resistance poses a severe threat to modern clinical medicine and public health. Understanding conjugation pathways helps researchers design novel strategies to block plasmid transfer in infections. Hospital environments often foster resistant strains due to the frequent selection pressure of antimicrobial drugs. Rarefaction is a statistical ecology term used to estimate species richness and has no role in genetics. Transduction involves bacteriophages accidentally transferring host bacterial DNA rather than direct cell contact. Transformation involves bacteria taking up naked extracellular DNA fragments directly from their surrounding environment.
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