1-3-2-4 here it is by birds u mean vulture right
Acetylcholine..
hope it helps
Bacterial flagellum is composed of protein flagellum which looks like hollow tube. It passes through protein rings (basal body rings) in the cell's membrane that act as bearings. Flagellum is long, filamentous and it rotates via motor which is located on the inner cell membrane. The motor is powered by proton motive force (flow of protons through the membrane due to a concentration gradient).
The endosymbiotic theory states that eukaryotic cells might have evolved from prokaryotic cells through a close realtionship.
Oxygen and glucose hope this helps