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 the calyx is not only characteristic, but pragmatic in terms of auditory chronological development. As a synapse, the calyx of Held follows a mechanism similar to other synapses. A thorough description can be found under neurotransmission. Calcium influx for the immature calyx of Held is mediated by N-, P/Q-, and R-type calcium channels; however upon maturation only P/Q-type calcium channels become dominant. Upon calcium influx, the immature calyx of Held is highly reactive due to its small calcium buffer ability – this causes the release of glutamate even at low levels of calcium influx. Within the terminal, as with other