Question

Resin ducts of Pinus are an example of
A. Lysigenous cavity
B. Schizogenous cavity
C. Vacuolated cells
D. Intercellular spaces

Answer 1

Resin ducts are elongated, tube shaped intercellular spaces which are surrounded by epithelial cells which secrete resin into the canal. These canals are found in between fusiform rays and are orientated longitudinally and radially present. Resin is antiseptic and aromatic which prevent the development of fungi and deters insects.

Complete answer:
The intercellular spaces are exceptionally well developed in aerenchyma of many aquatic plants. They form a connected system throughout the entire plant body. There are two types of spaces according to the mode of development which are schizogenous and lysigenous. Schizogenous is the most common which results from the separation of cell walls from each other along various areas of contact.
In schizogenous spaces, at the end of cell division a cell plate is formed which separates the two sister protoplasts. The plate helps in the formation of the middle lamella and the components of the cell wall deposit on the both sides of the middle lamella to form the primary cell wall. The new middle lamella develops with the help of deposits. There are various examples of this schizogenous cavity or duct which are ducts of Pinus, secretory ducts of Apiaceae and Asteraceae which are the secretory cavities of Eucalyptus etc.

Hence, the correct option is B. Schizogenous cavity.

Note: The cell wall separates and schizogenous spaces are formed. During differentiation to parenchyma, meristematic cells are tightly packed which lead to development of Schizogenous spaces which lead to formation of ducts and cavities in the plant body.