phytoplankton-> krill-> squid-> sea lion-> killer whale
which of the following would most likely be eradicated by the bioaccumulation of PCBs in the food chain shown above?
a- krill
b- squid
c- sea lion
d- killer whale
To determine which organism would most likely be eradicated by the bioaccumulation of PCBs in the given food chain, we need to understand what bioaccumulation is and how it affects organisms.
Bioaccumulation is the gradual buildup and concentration of substances, such as pollutants or toxins, in the tissues of organisms over time through the food chain. In this specific food chain, phytoplankton are consumed by krill, which are consumed by squid, which are consumed by sea lions, and finally, sea lions are consumed by killer whales.
PCBs (polychlorinated biphenyls) are synthetic organic pollutants that were widely used in the past and have been found to be persistent and accumulate in the environment. They are known to bioaccumulate in the fatty tissues of organisms and can have toxic effects, especially on higher trophic-level organisms.
Given the information above, we can determine that the highest trophic-level organism in the food chain, the killer whale, would most likely have higher levels of PCBs due to bioaccumulation. As organisms consume prey with PCBs, these substances accumulate in their tissues in higher concentrations.
Therefore, the correct answer is d- killer whale.