Question

The resin ducts of gymnosperms are
A. Lysigenous
B. Schizogenous
C. SchizoIysigenous
D. None of the above

Answer 1

Gymnosperms are the first land plants in which seeds are produced. The seeds are naked or unprotected as they are not enclosed in the fruits. The vegetative parts of a gymnosperm plant contain resin ducts. These ducts are may be lysigenous or schizogenous or schizolysigenous.

Step by step answer: The resin duct of gymnosperms is schizogenous as these cavities are formed by the split of common walls and the separation of masses of cells from one another during development. As a result, an intercommunicating system is formed between inter-cellular spaces and these cavities. Through this communication system, the gases and liquids can easily diffuse from one part of the plant body to the other. The resin ducts in the gymnosperms and the secretory ducts in the angiosperms such as sunflower are schizogenous cavities. Whereas lysigenous cavities are formed by breaking down and dissolving the entire walls of a mass of cells during development. Lysigenous cavities
are large irregular cavities. These cavities store water, gases, and essential oils. They act as
glands. Thus, option B. Schizogenous is the correct answer.
Additional Information:
Schizolysigenous cavity is formed by both dissolution of entire cells and separation of the middle lamella of the cell walls. An example of the schizolysigenous cavity is the secretory cavity in Citrus.

Note: Schizogenous ducts or cavities are formed when cells are separate from each other during development. This results in a cavity or duct that stores resins in the gymnosperms. It is different from the lysigenous cavity that mostly found in angiosperms.