Question

Frustule is referred to as
A. Silicated cell wall
B. Cellulosic cell wall
C. Stony cell wall
D. Lignified cell wall

Answer 1

Hint: Frustule is a hard cell wall which has pores in it. It is made up of silica. It is the characteristic feature of diatoms. It is involved in reproduction of diatoms and also involves excretion of wastes from their body.

Complete answer:
> Cellulosic cell wall is made up of cellulose. It is the main component of cell walls in plants. Frustles don’t have cellulose. That’s why option B is incorrect.

> Stony cell wall is found in some plant cells such as peaches fruit. It provides the toughness to the plant cell. It is not present in frustration. That’s why option C is incorrect.

> Lignified cell wall is made up of lignin. Lignin provides the mechanical support, and provides resistance to various stresses such as water. It is found in the xylem of plants. It is also found in cell walls of plants which are found in the dry condition for minimizing water loss. But frustules of diatoms don’t have lignin. That’s why option D is incorrect.

> Frustule is present in the diatoms. It is present in the cell wall of diatoms. It is made up of silica. Silica consists of silicic acid and a layer of organic substances. These are found to be the same as found in the cell wall of plants. There are two overlapping sections in the frustule. These overlapping structures are known as thecae or valves. The two theatres are joined by the band of silica. Silica holds together these two valves. The pores are present in the frustule which helps to remove the waste from the body of diatoms and secretion of mucilage.

Hence, The correct answer is option (A).

Note: The bands of silica are responsible for fitting the two thecae of frustule. The silica bands allow the diatom to produce new theca during reproduction. These frustules are found in the diatoms. Frustules are involved in excretion of wastes from the body.