Royal jelly, a thick, milky substance secreted by young nurse honeybees to feed a bee colonyâs larvae, most notably the queen larvae, is a rich source of nutrients, as well as acetycholine, a neurotransmitter that plays a critical role in cognitive function.
The origin of the eukaryotic cell is a milestone in the evolution of life, since eukaryotes include all complex cells and almost all multicellular organisms. The timing of this series of events is hard to determine; Knoll (2006) suggests they developed approximately 1.6â2.1 billion years ago.
1 They are unicellular prokaryotes-microbes without cell nucleus and any other membrane-bound organelles in their cells-and belong to the kingdom, Archaea. 2  They were first discovered in 1977 by Carl Woose and George E. Fox and classified as bacteria.