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 Organelles of Eukaryotic Cells Eukaryotic cells have a nucleus and internal organelles. 2  The external boundary of the cell, the perimeter of the nucleus, and the borders of the organelles are all made of faâ¦. large, double membrane-bound organelle found in eukaryotic cells.  Contains DNA and RNA. Organelle-A membrane-bound sub-cellular  structure found in eukaryotic cells.