The chemical reactions and pathways involving sphingolipids, any of a class of lipids containing the long-chain amine diol sphingosine or a closely related base (a sphingoid).

The vesicular release of classical neurotransmitter molecules from a presynapse, across a chemical synapse, the subsequent activation of neurotransmitter receptors at the postsynapse of a target cell (neuron, muscle, or secretory cell) and the effects of this activation on the postsynaptic membrane potential and ionic composition of the postsynaptic cytosol. This process encompasses both spontaneous and evoked release of neurotransmitter and all parts of synaptic vesicle exocytosis. Evoked transmission starts with the arrival of an action potential at the presynapse.

Fusion of intracellular membrane-bounded vesicles with the pre-synaptic membrane of the neuronal cell resulting in release of neurotransmitter into the synaptic cleft.

Fusion of the membrane of a synaptic vesicle with the presynaptic active zone membrane, thereby releasing its cargo neurotransmitters into the synaptic cleft.

The specific behavior of an organism during the emergence from an egg shell. In Drosophila for example, the larva swings its head reiteratively through a semicircular arc, using its mouth hooks to tear apart the chorion in front of it and thus free itself from within the egg shell.

Any process preventing the degeneration of the photoreceptor, a specialized cell type that is sensitive to light.

The chemical reactions and pathways resulting in the breakdown of ceramides, any N-acetylated sphingoid.

The space external to the outermost structure of a cell. For cells without external protective or external encapsulating structures this refers to space outside of the plasma membrane. This term covers the host cell environment outside an intracellular parasite.

All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.