The Protist Kingdom consists of mostly unicellular organisms that can have characteristics similar to plants, animals or fungi. Characteristics of Protists: mostly unicellular, few multicellular, eukaryotic, can be heterotrophic or autotrophic.Ex: algae, Paramecium, kelp (multicellular). î î î.he Protist Kingdom consists of mostly unicellular organisms that can have characteristics similar to plants, animals or fungi. Characteristics of Protists: mostly unicellular, few multicellular, eukaryotic, can be heterotrophic or autotrophic. Ex: algae, Paramecium, kelp (multicellular). î î î.
The active metabolites of codeine, notably morphine, exert their effects by binding to and activating the Î¼-opioid receptor. This occurs because opioids structurally mimic endogenous endorphins which are naturally found within the body and also work upon the Î¼-opioid receptor set.
Norcodeine also has a similar affinity to codeine for the mu opioid receptor [Article: 8818573 ]. Between 0-15% of codeine is O-demethylated to morphine, the most active metabolite, which has 200 fold greater affinity for the mu opioid receptor compared to codeine.