Streptanthus bracteatus Streptanthus bracteatus Streptanthus bracteatus is a species of flowering plant in the mustard family known by the common names bracted jewelflower and bracted twistflower. It is endemic to Texas in the United States. This annual or biennial herb has a branching stem up to 1.2 meters tall. It is hairless and generally waxy in texture. The basal leaves have lobed or toothed blades on long petioles, and the leaves higher on the stem have smooth or toothed edges. The inflorescence is a raceme of flowers and bracts. Each flower has a bell-shaped calyx of sepals and four purple petals which
Calyx of Held principal neuron with a distinct morphology: branching of the calyx allows the creation of second- and third-order networks. Each branch establishes a connection with the principal neuron, establishing a large number of active zones. This is unusual for synaptic terminals in the brain, as most create a single active zone. Each calyx contains anywhere from 300 to 700 active zones, and in each of the active zones there are about 100 glutamate-containing vesicles with about 3 docked vesicles at a time. These vesicles are large, consistent with the findings regarding quantal size in other adult synapses. Dense-core vesicles, usually containing