Plant Structures: Cells, Tissues, and Structures

pdf logoPrint this CMG GardenNotes

green line
green line

Plant cells are grouped into tissues based on similar characteristics, then into five distinct structures (organs).

  • Cells – Individual building blocks for life processes and growth. Common cells contain genetic matter (deoxyribonucleic acid, or DNA) and metabolic organelles but they are mostly water. In green plants, they are the site of sugar production (photosynthesis). [Figure 1]

plant cell

Figure 1.  Plant cell



  • Tissues – Groups of cells that are similar in appearance and function, for example:

  • Epidermis is the single exterior layer that protects the stems, leaves, flowers, and roots.  The outside surface of the epidermis tissue is usually covered with a waxy substance called cutin, which reduces water loss.

  • Parenchyma tissues are made of simple, thin-walled cells.  In a carrot, for example, the parenchyma cells become a storage unit called the cortex.  In leaves, a layer of parenchyma tissues under the epidermis is active in photosynthesis.  When wounded, parenchyma cells can become meristematic and proliferate to grow over the wound.

  • Meristematic tissues are comprised of actively dividing cells.

  • Sclerenchyma tissues are thick-walled support cells found throughout the plant as fiber.

  • Xylem is a structurally complex tissue that conducts water and nutrients from the roots to all parts of the plant.  The xylem is comprised of a series of long tubes made up of shorter vessel members.  In woody plants, the xylem tissue becomes the wood.

  • Phloemtissue conducts food and metabolites from photosynthesis throughout the plant, including down to the roots.

  • Structures (organs) – Groups of tissues working together with a common function, (e.g., roots, stems, leaves, flowers, fruits, and seeds).

  • Plant – Made up of a number of coordinated structures to form a working unit.

green line
green line

Authors: David Whiting, Consumer Horticulture Specialist (retired), Colorado State University Extension; with Michael Roll and Larry Vickerman (former CSU Extension employees).  Line drawings by Scott Johnson and David Whiting.

  • CMG GardenNotes are available online at www.cmg.colostate.edu
  • Colorado Master Gardener/Colorado Gardener Certificate Training is made possible by a grant from the Colorado Garden Show, Inc.
  • Colorado State University, U.S. Department of Agriculture, and Colorado counties cooperating
  • Extension programs are available to all without discrimination.
  • Colorado Master Gardener LogoNo endorsements of products mentioned is intended nor is criticism implied of products not mentioned.
  • Copyright. 2003-15. Colorado Master Gardener Program, Colorado State University Extension. All Rights Reserved. CMG GardenNotes may be reproduced without change or additions, for nonprofit educational use.

Revised September 2015

Updated Thursday, January 14, 2016 by Mary Small

green line