Antimycin A Antimycin A is used in catfish farming: added to the water at 10 ppb, it kills small fish but does not harm catfish. Thus, small fish die out, and catfish get all the resources. When Antimycin A is added to isolated mitochondria, NADH and succinate both accumulate. However, if ascorbate, an artificial redox mediator that transfers electrons to cytochrome c, is added, oxygen consumption is still observed. Which step in the respiratory chain is antimycin A likely to inhibit (1 pt)

Inhibits electron transport chain in mitochondria.

Explanation:

Antimycin A inhibits electron transport chain which leads to the complete halt of electron transport in mitochondria. due to this inhibition of electron transport chain in mitochondria leads to the killing of the fishes except catfish and so the catfish increase in population due to more resources and no competition. this Antimycin A is highly toxic for fishes and kill all fishes if used at the amount of 10 ppb.

when it is at an intermediate population density

i think this picture will you.