Neurotransmitters are formed in a presynaptic neuron and stored in small membrane-bound sacks, called vesicles, inside this neuron. When this neuron is activated, these intracellular vesicles fuse with the cell membrane and release their contents into the synapse, a process called exocytosis.
Modern timekeeping defines a day as the sum of 24 hours â but that is not quite correct. The Earth's rotation slows down over time. So in terms of solar time, most days are a little longer than 24 hours.
A mean sidereal day is 23 hours, 56 minutes, 4.0916 seconds (7001239344699000000â 23.9344699 hours or 6999997269580000000â 0.99726958 mean solar days), the time it takes Earth to make one rotation relative to the vernal equinox.