Question

Coir is obtained from which of the following fruits is part of coconut?
A. Seed coat
B. Epicarp
C. Mesocarp
D. Endocarp

Answer 1

Hint: It is a tropical plant of the Arecaceae family and the fruit is referred to as drupe, not a true nut.

Complete answer:
Coir is a natural fiber extracted from the mesocarp of the coconut fruit that is present between the hard, internal shell and the outer coat of a coconut. Coir is made up of lignin which is a woody plant substance, and cellulose. Coconut fruit is made up of three layers such as exocarp, mesocarp, and endocarp. The exocarp is the outer green covering, the mesocarp is the fleshy part that becomes husk after drying and the endocarp is the woody inner part.

Additional information:
- Coir is used in horticulture in potting compost, mainly in orchid mix.
- The processed fibers are ranging from about 4 to 12 inches in length.
- They are light in weight, brittle, strong, and elastic, and have a tendency to curl.
- The pH of the coir ranges from 5.6 to 6.9, and in commercially available sources it ranges from 5.8 to 6.5.
- They are tough to abrasion and can be dyed.
- Coir protects the nut against heat from severe solar radiation and mechanically if it falls to the ground.
- Coconut fiber has been used for manufacturing rope, mats and carpeting
- It has a significantly higher water-retention capacity than Rockwool.
- It decomposes slowly with respect to time due to its structure that contains more than 45 percent woody lignin.
- Coir is completely natural fiber and it has no biohazard or disposal problems.

Figure: Structure of coconut

Note:
- In coconut plants, the water inside the coconut is a free nuclear endosperm and the adjacent white kernel is the cellular endosperm.
- In coconut, endosperm persists in the mature seed and it is used up during seed germination.