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.
Many evolutionists believe Lynn Margulisâ idea that eukaryotic cells came about as a prokaryotic cell âateâ (by a process called endocytosis) other prokaryotic cells, which then became the mitochondria and chloroplasts.