Sclereids can have many different forms and occur throughout the plant. Fibers in contrast, are thin and elongated cells usually associated with vascular tissues. The two main vascular tissues are the xylem and phloem. The xylem distributes water and mineral nutrients from roots to the rest of the plant, while the phloem is responsible for the transport of the products of photosynthesis and other organic molecules throughout the plant. The tracheids and vessel elements are the conducting elements of the xylem .
Gymnosperms only have tracheids in their xylem, while angiosperms have both.
Storage parenchyma cells and fibers are found next to tracheids and vessels to form the xylem. They also stack in vertical rows to form sieve tubes. The sieve elements or cells are alive at maturity but lack nucleus and central vacuoles and have few cytoplasmic organelles. They assist in the transport function of the phloem. The objective is today's lab is to familiarize yourself with the basics of plant morphology and anatomy.