Traditionally, some textbooks from the United States used a system of six kingdoms (Animalia, Plantae, Fungi, Protista, Archaea/Archaeabacteria, and Bacteria/Eubacteria) while textbooks in Great Britain, India, Australia, Latin America and other countries used five kingdoms (Animalia, Plantae, Fungi, Protista and Monera).
For other uses, see Placebo (disambiguation) and Placebo effect (disambiguation). The placebo effect can be produced by inert tablets, by sham surgery, and by false information, such as when electrical stimulation is turned off in those with Parkinson's disease implanted brain electrodes.
Placebo Effect in Depression Treatment Â». A placebo is a substance, such as a pill or shot, that doesn't contain any active medicine. Scientists typically use placebos as controls in research studies. This helps them understand how much of a medicine's effects are due to the drug itself,...