kerato- or kerat- also cerato- or cerat- pref. 1. Horn; horny: keratosis. 2. Cornea: keratectomy. [Greek kerÄto-, horn, from keras, kerÄt-; see ker- in Indo-European roots.] kerato- or before a vowel kerat- combining form 1. indicating horn or a horny substance: keratin; keratogenous. 2. (Medicine) indicating the cornea: keratoplasty. [from Greek kerat-, keras horn] kerato- a combining form meaning âcorneaâ: keratoplasty.
Early root growth is one of the functions of the apical meristem located near the tip of the root. The meristem cells more or less continuously divide, producing more meristem, root cap cells (these are sacrificed to protect the meristem), and undifferentiated root cells.
As a complex tissue, it is composed of four cell types: vessel elements, tracheids, parenchyma cells and fibers. Vessel elements, non-living, barrel-like cells, and tracheids, non-living, tapered cells, are the actual water-conducting cells of xylem tissue. The parenchyma cells function in storage and the fibers function in support. Phloem transports the carbohydrate products (sugars) of photosynthesis throughout the plant.