Angelica acutiloba with distinct calyx and white corolla. However, the calyx is often reduced with obsolete calyx teeth. The flowers have five petals, sepals, and stamens. The white petals are often obovate to oblong. The inflorescences contain fifteen to forty-five pubescent rays, 1–10 cm in length, which surround about thirty small disk flowers. The peduncles which hold the entire inflorescence are glabrous or pubescent and 5–20 cm long. While the stalks of each single flower in the flower clusters called pedicels, are thin and often sessile. The whorl of bracts beneath the inflorescences is called involucre. It consists of phyllaries, modified bracts,
Calyx of Held The first is that in the second week of development, myelination of the VCN axons in the MNTB increases. This prominent growth in myelin corresponds to the chronological development of the signaling circuit and adaptation of the calyx. The second ultrastructural change involves the principal neurons of the MNTBs, whose cell bodies and nuclei increase in surface area due to enlargement. This is a direct result of individual, larger postsynaptic densities breaking up into smaller, multiple densities. Potassium channels are vital in conducting the presynaptic action potential. The calyx contains several types of potassium channels, each differing in location and