Tissue Culture Terminology

Plant tissue culture - a collection of techniques used to maintain or grow plant cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition

Callus - Undifferentiated, swollen cell mass forming under the influence of elevated plant hormone levels.

Etiolation - Yellow and stretched plant; parts elongate until light is intercepted.

Explant - Part of an organism used in "in vitro" culture.

IAA - Indoleacetic acid; a plant hormone increasing cell elongation and, under certain circumstances, implicated in stimulating cell division and root formation. IAA moves in a polar manner in plants forming an IAA gradient in tissues. Orientation of plant organs, then, influence callus formation and morphogenesis.

"in vitro" - "In glass"; as in tissue culture methods

Morphogenesis - Change in shape

Polarity - Orientation in gravitational field.

Primordia - The earliest detectable stage of an organ, such as a leaf, root or root branch.

Root Hairs - Epidermal cell extensions of
young root that increase absorptive surface area.

Totipotency - The establishment of missing plant organs or parts; formation of a whole plant from a few cells or small portion of a plant.

Wound Response - Formation of callus in wounded area

Micro propagation - the practice of rapidly multiplying stock plant material to produce a large number of progeny plants, using modern plant tissue culture methods

Protoplasts - plant cells without cell walls

Asepsis - the state of being free from disease-causing micro-organisms (such as pathogenic bacteria, viruses, pathogenic fungi, and parasites)

Laminar flow cabinet or laminar flow closet or tissue culture hood - a carefully enclosed bench designed to prevent contamination of semiconductor wafers, biological samples, or any particle sensitive materials

Agar or agar-agar - a jelly-like substance, obtained from algae

Parenchyma - one of the three main types of ground tissue, and the most common. It can be distinguished through their thin cell wall as compared to other cells. Parenchyma cells make up the bulk of the soft parts of plants, including the insides of leaves, flowers and fruits

Auxin - plant hormone that causes the elongation of cells in shoots and is involved in regulating plant growth.

Meristem - the tissue in most plants containing undifferentiated cells (meristematic cells), found in zones of the plant where growth can take place.

Organogenesis - is simply the process of forming new organs, occurs continuously and only stops when the plant dies