Question

The secretory cells of the plants are -
(a)Nectary cells
(b)Hydathode
(c)Laticifer cells
(d)All of the above

Answer 1

Plants have multiple secretory cells that fulfill different functions. The functions include producing substances to attract pollinators, animals, production of secondary metabolites, releasing some substances after an injury.

Complete answer:
- Secretory cells in plants are concerned with the secretion of excretory products, excess ions or sugars, and alkaloids and other secondary metabolites.
- Nectary cells or nectaries are glands present on the surface of plant parts that secrete nectar which is a liquid that contains sugar.
- Hydathodes are secretory structures which are a modification of tissues of leaves, present on tips and margins, that discharge water from the interior of the leaf to the surface in a process known as guttation.
- Laticifers are cells that contain latex, a milky or clear, colored or colorless liquid. The cells secrete this latex when under pressure and the part of the plant containing them is cut.
- Hence, all of these are secretory cells in plants.

Additional Information: - Secretory tissues in plants are of two types: Glandular tissues which consist of glands and trichomes; and laticiferous tissues which consist of ducts and laticifers.
- Secretions can be intracellular where they occur within cells or extracellular where the secretion goes from the cell to the environment.
- Secretion occurs by exocytosis or diffusion (passive transport).
- Other external secretory structures include trichomes, glands, and osmophores. Other internal secretory structures include secretory cells, cavities, and canals.

So, the correct answer is ‘all of the above’.

Note: - Latex of various plants consists of water, terpenes, sugars, enzymes, etc.
- Apart from leaves, stems are known to produce secretory substances.
- Plants like foxglove and others from Urticaceae secrete substances to trap and digest insects.