Plant cell the major classes of cells and tissues of roots, stems, leaves, flowers, and reproductive structures, each of which may be composed of several cell types. Parenchyma cells are living cells that have functions ranging from storage and support to photosynthesis (mesophyll cells) and phloem loading (transfer cells). Apart from the xylem and phloem in their vascular bundles, leaves are composed mainly of parenchyma cells. Some parenchyma cells, as in the epidermis, are specialized for light penetration and focusing or regulation of gas exchange, but others are among the least specialized cells in plant tissue, and may remain totipotent, capable of
Guidepost cells cellular substrates to attract LOX axons. To test their role in guidance, scientists (Sato and colleagues) ablated lot cells with a toxin called 6-OHDA. As a result, LOT axons were stalled in the areas where lot cells were destroyed, which confirmed lot cells as guidepost cells. Cajal-Retzius cells are the first cells to cover the cortical sheet and hippocampal primordium, and regulate cortical lamination by Reelin. In order to make connections with GABAergic neurons in different regions of the hippocampus (stratum oriens, stratum radiatum, and inner molecular layer), pioneer entorhinal neurons make synaptic contacts with Cajal-Retzius cells. To test their