Internal Parts of Plants.

The internal workings of a plant are intriguing examples of functional design. Like other living organisms, the tissues and organs organize from cells. The combination of structures all serve a specific purpose, and while there are various types of plant cells, all contain equal DNA. This makes it possible for each cell to contain all the information necessary to replicate the plant in its entirety.

Parenchyma Cells

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  The single cell parenchyma are the most common cells found within a plant. Parenchyma cells have thin walls and form the bulk of the plant body. In some areas that get light, such as the leaves, parenchyma cells control photosynthesis. In deeper plant areas, where light is inaccessible, these cells function as storage. The cells, which are also involved in cellular respiration and the metabolic processes, are found in the soft, fleshy tissue of fruits and seeds. These cells reproduce throughout their lifetime.

Collenchyma Cells

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  The thick walls of the collenchyma cells provide support and stability for the plant. They are arranged in strands and are elongated or cylindrical in shape. These are flexible cells made from cellulose. The cells are found on the corners of angular stems, in the stem stalk, or as part of vascular bundles. They are generally found in areas of plant growth.

Sclerenchyma Cells

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  Sclerenchyma cells function as plant support. Hardened with lignin, a tough subtance that strengthens the cell wall, these cells are thicker and less flexible than the collenchyma cells. The cells usually do not live after they are fully grown, but the non-living cell structure will remain as a source of strength. These cells are found in stems, leaf veins and in the hard outer covering of seeds and nuts.

Xylem

• The tissue xylem functions as water and nutrient transport. It also provides structural support to the plant. The xylem is composed of empty cells that die upon maturity. They form a strong cylindrical tube that runs the length of the plant. Water and minerals are pulled through the xylem by the physical force of tension.

Phloem

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  Phloem transports the amino acids and sugars the plant makes through photosynthesis. Food and nutrients are moved from their source, at the leaves of the plant, to areas of storage or use. Phloem is made up of sieve cells and companion cells. Sieve cells are mostly empty cells with openings so food can move from one cell to another. Companion cells assist the movement of photosynthetic products into the sieve cells. Plant hormones and waste products are also redistributed through the phloem.

Meristematic Tissue

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  The cells of this tissue are small and thin-walled. The meristematic tissue controlsgrowth of flowers, fruits and areas near the xylem and phloem that influence the girth of the plant.