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.
Tissue types. The major classes of cells differentiate from undifferentiated meristematic cells (analogous to the stem cells of animals) to form the tissue structures of roots, stems, leaves, flowers, and reproductive structures. Xylem cells are elongated cells with lignified secondary thickening of the cell walls.