Passage:
Until the late twentieth century, oceanic carbon cycle models treated marine bacteria primarily as mineralizers that converted dissolved organic matter into inorganic nutrients, which were then consumed almost exclusively by higher trophic levels through the grazing chain. However, the discovery of abundant marine bacteriophages—viruses that infect bacteria—prompted a fundamental revision of this classic paradigm. By lysing microbial hosts, bacteriophages release cell contents back into the water column as dissolved organic carbon, effectively preventing that carbon from moving up the food web to larger organisms. This phenomenon, known as the 'viral shunt,' redirects organic matter away from macro-organisms and back into the microbial loop, accelerating local nutrient regeneration while simultaneously reducing the efficiency of the biological carbon pump that sequesters carbon in the deep ocean. Consequently, recent biogeochemical frameworks have integrated viral dynamics not merely as minor biological disturbances, but as key regulators of global carbon flux.
Based on the passage, which of the following statements accurately describe the passage's primary purpose and main argument?
Select all that apply.
- To highlight how recent insights into viral activity led scientists to revise traditional models of oceanic carbon cycling.Cevap
- BTo detail the specific molecular mechanisms by which bacteriophages penetrate microbial cell walls in deep-sea habitats.
- To explain how the viral shunt alters the movement of organic matter within marine food webs.Cevap
- DTo argue that viral lysis is the primary cause of carbon sequestration failure across all planetary ecosystems.
- ETo criticize earlier oceanographers for systematically ignoring microbial contributions to nutrient cycles out of scientific negligence.