Theories Behind Plant Tissue Culture Glossary

acid

A chemical compound that can donate a proton

acidic

Having a pH lower than 7, having a higher concentration of H+ ions.

amino acids

The basic building blocks of proteins. The sequence of amino acids in a protein and protein function are determined by the genetic code.

autoclaving

A treatment of solutions, tools and containers with high temperature (usually at 120oC) under high pressure (usually at 1.05 kg/cm2) to eliminate organic contaminations.

callus

A mass of undifferentiated cells used in tissue culture.

cofactor

The nonprotein component of an enzyme. They often carry out activities for which amino acids are not suited.

de-differentiation

The developmental process from a highly differentiated cell to an undifferentiated cell. It is a reverse to differentiation.

differentiation

The developmental process that specializing cells' function and shape.

electron transfer

The transfer of electrons between a series of components in a controlled fashion. Examples include the mitochondrial electron transfer chain involved in oxidative phosphorylation and the chloroplast electron transfer chain carrying out photophosphorylation. Electrons are transferred from molecules with a higher free energy to those with a lower free energy.

environment

The combinations of all the conditions external to the genome that potentially affect gene expression.

enzymes

Special protein molecules which function in catalyzing chemical reactions.

explants

A piece of plant tissue cut for tissue culture.

gene

The fundamental unit of heredity that carries genetic information from one generation to the next. A gene is an ordered sequence of nucleotides located on a particular position on a particular chromosome that encodes a specific functional protein.

genes

The fundamental unit of heredity that carries genetic information from one generation to the next. A gene is an ordered sequence of nucleotides located on a particular position on a particular chromosome that encodes a specific functional protein.

genetic engineering

The process of adding foreign DNA to the genome of an organism.

genome

All the genetic material in the haploid set of chromosomes for a particular organism.

genotype

The allelic composition of a cell or organism.

growth regulators

(also called plant hormones) are numerous chemical substances that profoundly influence the growth and differentiation of plant cells, tissues and organs. Plant growth regulators function as chemical messengers for intercellular communication 

hyperhydricity

A network formed by hydroxyl connection.

in vitro

In an experimental situation outside the organism (literally, "in glass").

inducing medium

The tissue culture media for helping the start of organ or embryonic cell development.

metabolism

A general term referring to the change of a herbicide from an active to an inactive state.

monopolar

Develop or move toward one direction.

morphogenesis

The process of morphology development.

MS medium

A popular plant tissue culture medium developed by T. Murashige and F. Skoog.

osmoticum

Particles that cause osmosis.

phloem

Tissue used for the movement of sugars from source tissue to sink tissue; Composed of living cells called sieve elements that have no nuclei, vacuoles, or ribosomes. The ends of the sieve elements contain connective pores, which join them together to form tube-like structures.

polarity

Property of a covalent bond or an entire molecule that results in a negative pole and a positive pole; A bond becomes polar if the electrons involved in the bond are not shared equally. Polarity results when the center of the negative charge does not coincide with the center of the positive charge.

proembryonal complex

A mass of embryogenic cells.

progenitor cell

A cell that is able to produce embryogenic cells by cell division.

protein

A large molecule composed of one or more chains of amino acids in a specific order. Proteins are necessary for the structure, function, and regulation of an organism's cells, tissues, and organs. Each protein has a unique function determined by its shape.

protein synthesis

The production of proteins in a cell. Proteins are chains of amino acids linked in the order determined by the genetic code.

proteins

Large molecules composed of one or more chains of amino acids in a specific order. Proteins are necessary for the structure, function, and regulation of the organism's cells, tissues, and organs. Each protein has a unique function determined by its shape.

protoplast

A plant cell that has had the cell wall removed.

reduction

The opposite of oxidation. When a molecule acquires one or two electrons it becomes more reduced.

secondary embryogenesis

The development of embryos from young embryos.

selective

A herbicide that is toxic to certain plants but harmless to others.

tissue culture

Plant cells are grown in culture which allows them to be manipulated and then induced to develop into whole plants.

totipotency

The ability of a single plant cell to grow, divide, and differentiate into an entire plant. Mammalian cells do not have this ability.

transforming

The process of introducing foreign DNA into an organism which is then passed on to the organism’s progeny.

transgenic

An organism that has a new genetically engineered DNA sequence found in every one of its cells. Genetically engineered organisms are transgenic. These two terms are used interchangeably.

undifferentiated

Cells that have not developed into specialized tissues. Undifferentiated cells, called callus, are used in tissue culture during the transformation process.

vacuolate cell

A cell derived from a progenitor cell during embryogenesis and having a large vacuole. Vacuolate cells usually are larger than cytoplasmic cells which result from the same cell division.

variety

Crop plants within a species that have the same genetic composition. Because plants in a variety are usually heterozygous, their offspring will not remain genetically pure (i.e., corn hybrid varieties).

zygote

The cell formed when the egg and sperm fuse. The cell has two copies of each chromosome (2n) and will continually divide to develop into an entire organism.