Silene invisa cyme of up to three flowers at the top of the stem. Each flower has a bell-shaped calyx of fused sepals lined with ten green veins and covered in short, glandular hairs. The strap-shaped or rectangular petals have blunt tips or may be notched. They are whitish to pinkish or lavender and sometimes barely protrude from the calyx. Silene invisa Silene invisa is a species of flowering plant in the pink family known by the common names red fir catchfly and short-petaled campion. It is endemic to California, where it is known only from the southernmost Cascade Range and northernmost
Calyx of Held calcium into the mitochondria, and providing energy for glutamate synthesis. Various glial cells are also associated with the calyx of Held. Two types of glial cells surround the calyx: astrocytes and NG glial cells. The astrocytes express glutamate transporters to remove glutamate from the synapse. This is the only known mechanism for removal of glutamate from the synapse. The NG glial cells express AMPA receptors. At postnatal day two (P2), the immature calyx of Held is formed, easily distinguished by its characteristic sealed-spoon morphology. The primary synaptic contacts that form the calyx are assembled between neurons of the MNTB (medial