Plant Tissues

Plant Tissues

Simple Tissues

Parenchyma

• Perform most metabolic functions in the plant
• Create and store organic products Example: these cells contain the Chlorophyll in leaves Example: these cells store the starch in roots
• Thin cell wall
• Alive at maturity
• Most cells can differentiate into other types of plant cells when needed

Collenchyma

• Groups of flexible elongated cells (strands)
• Provides flexible support for young plants

• Rigid cells that provide structural support
• Contains Lingin: strong polymer for support
• Many are dead at maturity
• Unable to grow / elongate
• Specialized cells for structural support
• Sclerids: boxy, thick and irregular
• Fibers: long slender groups of strands Example: Hemp fibers are used to make rope and clothing

Photo by CNX OpenStax | CC BY

Complex Tissues

Xlyem

• Water-conducting cells
• Specialized elongated cells
• Dead at maturity
• Hollow cell walls transport water throughout plant
• Tracheids: long, thin and tapered cells with pits for water to move to other cells
• Vessel elements: wider and thicker cells for long distance water transport

• Sugar-conducting cells
• Specialized elongated cells
• Alive at maturity
• Composed of sieve-tube elements
• lack nucleus, ribosomes, vacuole and cytoskeleton
• improves movement of sugars through cell
• Sieve Plates: ends of the cells with pores to allow fluid to pass through
• Companion Cells: surround the sieve-tube elements and facilitate sugar loading