Heterotrophs异养生物 Secondary producer,consumer Animals,fungi, most bacteria, many protoctists and a few plants cannot synthesize their organic molecules from inorganic ones.They need to take in an external source of organic carbon.These organ-isms are heterotrophs. Heterotrophs Heterotrophs 异养生物 Secondary producer, consumer Animals, fungi, most bacteria, many protoctists and a few plants cannot synthesize their organic molecules from inorganic ones. They need to take in an external source of organic carbon. These organ-isms are heterotrophs