1. Secretory Tissue
The tissues that are concenered with the secretion of secretory materials namely gums, resins, volatile oils, necter, latex and other substances are called secretory tissues.

2. External Secretory structures
May be :
Epidermal in origin
Sub-epidermal layers

4. Types of External Secretory Structure
Trichomes and glands
Digestive glands
Stinging hairs
Nectaries
Osmophores
Hydathodes
Unicellular hydathodes
Trichome hydathodes
Hydathodes with water conducting elements

11. Internal Secretory Structure
Secretory cells
Oil glands
Laticiferous tissue
Articulated
Non-articulated

13. Laticiferous tissue
These are found in many flowering plants, the substances may be whitish, yellow or pinkish in color
This is viscous fluid and established to be colloidial in nature
Many substances like sugars, proteins, gums alkaloid in nature
Remain suspended in matrix of water fluid

14. Articulated Latex
They contain numerous nuclei in the thin layer of cytoplasm along the cell wall
They act as a food storage organ or as reservoirs of waste products

15. Non-articulated Latex: Ducts or latex cells
These ducts are independent units which extend as branched structures for long distances in the plant body

16. Types of Latex
Articulated-
Nonarticulated