Jacksonia (plant) Jacksonia (plant) Jacksonia is a genus of about forty, mostly leafless broom-like shrubs or small trees in the flowering plant family Fabaceae. The genus is endemic to Australia and species occur in a range of habitats in all Australian states except South Australia. Plants in the genus "Jacksonia" are mostly leafless shrubs or small trees with rigid branches, and leaves reduced to small scales. The flowers are arranged in spikes or racemes with small bracts or bracteoles. The sepals are joined to form a short tube and the petals are usually shorter than the sepals. The standard or banner petal
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.