Streptanthus barbatus bristly edges (no more than 3 centimeters long) and borne on short petioles. Leaves above these are oval to rounded and may clasp the stem. Flowers occur at intervals along the upper stem. Each has a spherical to urn-shaped calyx of keeled sepals under a centimeter long with curving petals barely emerging from the tip. The calyx of sepals is whitish, darkening purple in maturity. The petals are purple. The fruit is a long, flat, curving silique which may be 7 centimeters in length. Streptanthus barbatus Streptanthus barbatus is a species of flowering plant in the mustard family known by
Calyx of Held sensitivity. Both low-threshold K channels and high-threshold delayed rectifier-type K channels are present in presynaptic neurons. There are four low-threshold K channels present: K1.1, K1.2, K1.3, and K7.5. K1.1 and K1.2 are located in the transition zone between the axon and the terminal, while K1.3 K7.5 are located in the calyx. There is a calcium activated potassium channel expressed in the calyx, however this type of channel does not contribute to neurotransmitter release. Within the span of one week, mice subjects (P7 to P14) showed that the density of the K1 and K3 low threshold channels increases, which in turn