4. Growth - An irreversible increase in size and is brought
about by the combined effects of cell enlargement and cell
division.
5. In a plant cell, growth starts with an increase in turgor
pressure leading to the stretching of cell wall.
Followed by protein synthesis which brings the production
of new cell wall materials and an increase in cytoplasmic
contents.
Then followed by cell differentiation where different cell
types are formed.
6. Tissue differentiation eventually leads to organ formation
and he development of new structure.
This last process is referred to as plant morphogenesis and
is responsible for overall form of the plant.
7. Auxin – is the name given to substances that can stimulate
elongation in celeoptiles.
(Coleoptile is the pointed protective sheath covering the emerging
shoot in monocotyledons such as grasses.)
8. Cytokinins – substance that trigger the cell divisions and
the naturally occurring cytokinins in plants is Zeatin.
(Zeatin is a plant hormone derived from the purinebase
called adenine.)
Gibberellins – are substance that stimulate stem elongation
through cell elongation and cell division.
9. Ethylene – is the gaseous plant growth regulator. It is
produced by wounded tissues, ripening fruits and aging plant
parts.
Abscisic Acid – another growth inhibitory hormone.
Brassinosteroids – another group of hormones named
after the plant they were first discovered.
