a) Rotenone is an isoflavone used as insecticide and pesticide. It works by interfering with Electron transport chain in mitochondria. It inhibits the transfer of elctrons from Complex 1 toUbiquinone. It is mildly toxic to humans and other mammals. But highly toxic to fish and insects because it is easily taken up through the gills or trachea but not through skin or gastrointestinal tract. The inhibition of NADH dehydrogenase by Rotenone decreases the rate of electron flow which inturn decreases the ATP production. If it does not meet ATP requirements the organisms die. b) Antimycin A binds to the Qi site of cytochrome reductase in the mitochondrial complex 3 and inhibits the oxidation of Ubiquinol. It strongly inhibits the oxidation of reduced Q in the respiratory chain severely limiting the rate of electron transfer and ATP production. c) Rotenone inhibits electron flow through complex1 whereas Antimycin Ainhibits electron flow through NAD linked complex 1 and also at complex 2 from succinate and fatty acyl coA through FAD. So, Antimycin A is more potent poisonous. Solution a) Rotenone is an isoflavone used as insecticide and pesticide. It works by interfering with Electron transport chain in mitochondria. It inhibits the transfer of elctrons from Complex 1 toUbiquinone. It is mildly toxic to humans and other mammals. But highly toxic to fish and insects because it is easily taken up through the gills or trachea but not through skin or gastrointestinal tract. The inhibition of NADH dehydrogenase by Rotenone decreases the rate of electron flow which inturn decreases the ATP production. If it does not meet ATP requirements the organisms die. b) Antimycin A binds to the Qi site of cytochrome reductase in the mitochondrial complex 3 and inhibits the oxidation of Ubiquinol. It strongly inhibits the oxidation of reduced Q in the respiratory chain severely limiting the rate of electron transfer and ATP production. c) Rotenone inhibits electron flow through complex1 whereas Antimycin Ainhibits electron flow through NAD linked complex 1 and also at complex 2 from succinate and fatty acyl coA through FAD. So, Antimycin A is more potent poisonous..

1. a) Rotenone is an isoflavone used as insecticide and pesticide. It works by interfering with
Electron transport chain in mitochondria. It inhibits the transfer of elctrons from Complex 1
toUbiquinone. It is mildly toxic to humans and other mammals. But highly toxic to fish and
insects because it is easily taken up through the gills or trachea but not through skin or
gastrointestinal tract. The inhibition of NADH dehydrogenase by Rotenone decreases the rate of
electron flow which inturn decreases the ATP production. If it does not meet ATP requirements
the organisms die.
b) Antimycin A binds to the Qi site of cytochrome reductase in the mitochondrial complex 3 and
inhibits the oxidation of Ubiquinol. It strongly inhibits the oxidation of reduced Q in the
respiratory chain severely limiting the rate of electron transfer and ATP production.
c) Rotenone inhibits electron flow through complex1 whereas Antimycin Ainhibits electron flow
through NAD linked complex 1 and also at complex 2 from succinate and fatty acyl coA through
FAD. So, Antimycin A is more potent poisonous.
Solution
a) Rotenone is an isoflavone used as insecticide and pesticide. It works by interfering with
Electron transport chain in mitochondria. It inhibits the transfer of elctrons from Complex 1
toUbiquinone. It is mildly toxic to humans and other mammals. But highly toxic to fish and
insects because it is easily taken up through the gills or trachea but not through skin or
gastrointestinal tract. The inhibition of NADH dehydrogenase by Rotenone decreases the rate of
electron flow which inturn decreases the ATP production. If it does not meet ATP requirements
the organisms die.
b) Antimycin A binds to the Qi site of cytochrome reductase in the mitochondrial complex 3 and
inhibits the oxidation of Ubiquinol. It strongly inhibits the oxidation of reduced Q in the
respiratory chain severely limiting the rate of electron transfer and ATP production.
c) Rotenone inhibits electron flow through complex1 whereas Antimycin Ainhibits electron flow
through NAD linked complex 1 and also at complex 2 from succinate and fatty acyl coA through
FAD. So, Antimycin A is more potent poisonous.