What is a plant hormone? Name four plant hormones. State one function of each.

Plant hormones (also known as phytohormones) are chemicals that regulate plant growth.

4 Plant hormones:
(a) Auxins: Influence cell enlargement, bud formation and root initiation. Also promotes apical dominance.

(b) Cytokinins: Influence cell division and shoot formation.

(c) Gibberellins: Stimulate cell elongation and initiate mobilization of storage materials in seeds during germination.

(d) Ethylene: Stimulates the ripening of fruit and initiates abscission of fruits and leaves.