A meristem's the tissue in all plants consisting of undifferentiated cells (meristematic cells) and found in zones of the plant where growth can take place. The term “meristem” was first used by Karl Wilhelm von Nägeli (1817-1891) from his book “Beiträge zur Wissenschaftlichen Botanik” in 1858. It's derived from the Greek word “merizein”, meaning to divide in recognition of its inherent function. Differentiated plant cells generally can't divide or… (More on Procambium)