Question

Longest plant cells are
A. Vessels
B. Tracheids
C. Cotton fiber
D. Fibres of Ramie

Answer 1

Hint: Just like humans, even in plants, plant cells are the basic and fundamental unit of plants. The cells found in plants are eukaryotic as they have nucleus and they also possess cell walls in addition to cell membrane.

Complete Answer:
Ramie fiber is one of the oldest plant fiber, which has been used for years to obtain fiber. The ramie plant has been cultivated in eastern Asia. The Ramie plant has various desirable properties, such as strength and durability due to which, it has frequently been used as a textile fiber of great potential.

Option a: Vessels are also known as trachea, are the most specialized and efficient conducting structure of xylem. It is typically found in angiosperms but absent from most gymnosperms such as conifers. The length of vessels varies from two cells to rows several meters long.

Option b: Tracheids are elongated cells in the xylem of vascular plants that serve in the transport of water and mineral salts. They are less than 6 mm in length.

Option c: Cotton fibers are natural hollow fibers. They are soft and cool. They are also known as breathable fibers and absorbent. Cotton fibers can hold water 24–27 times their own weight. The length of long-staple cotton is between 3cm to 6.35cm.

Option d: Fibers of Ramie are the longest plant cells with the length averaging 13 to 15 cm (5 to 6 inches) in length. It is elongated by intercalary growth and intrusive tip growth. Its fiber is pure white in color, lustrous, and moisture absorbent.

Thus, the correct option is d) Fibers of Ramie.

Note: It is to be noted that Ramie fiber is resistant to mildew and other types of microorganisms attack and it does not change color with prolonged exposure to sunlight.