Streptanthus farnsworthianus at intervals along the upper stem with one or two leaflike purple bracts at the base of the raceme. Each flower has an urn-shaped calyx of purple sepals up to a centimeter long. Curling purple-veined white petals emerge from the tip of the calyx. The fruit is a straight or curving silique up to 12 centimeters long. The plant was named for Evalyn Lucille Klein Farnsworth, a foothills cattle rancher and plant collector who first discovered it growing on her land. Streptanthus farnsworthianus Streptanthus farnsworthianus is an uncommon species of flowering plant in the mustard family known by the common
Calyx of Held embryonic calyx formation. One characteristic that distinguishes Eph proteins and their receptors from other signaling systems is their ability to transmit information bidirectionally. Forward and reverse signaling in VCN and MNTB cells is essential for the proper number and formation of VCN and ipsilateral MNTB projections in the calyx. Eph proteins also ensure that while axons pass through the ipsilateral MNTB, branching and final termination of these projections only occur in the contralateral MNTB, possibly because the proteins are only targeted towards specific regions on the axons. Overall, there are two ultrastructural changes that occur in the calyx of Held.