Fill in the blanks.
(a) Cork cells possess ____ on their walls that makes them impervious to gases and water.
(b) ____ have tubular cells with perforated walls and are living in nature.
(c) Bone possesses a hard matrix composed of ____ and ____.

Correct Answer:

(a) Cork cells possess suberin on their walls, making them impervious to gases and water.

(b) Sieve tubes have tubular cells with perforated walls and are living in nature.

(c) Bone possesses a hard matrix composed of calcium and phosphorus.

Explanation:

Suberin is a lipophilic macromolecule, responsible for providing insulation and protection to plant cell walls. It provides a uniform thickening of suberin to sclerenchyma tissue. 

Sieve tubes (Phloem) tissues transport food in the plants. Phloem transports food from leaves to all parts of the plant including roots.