16.An organised and differentiated cellular structure having Cytoplasm but no nucleus is called as: A. Tracheids B. Vessels C. Sieve tubes D. Xylem parenchyma
Option C The main function of phloem is to conduct food materials, usually from the leaf to other plant parts (e.g., storage organ and growing regions). Phloem consist of 4 types of cells: Sieve cell (in gymnosperms and pteridophytes)/ Sieve tube (in angiosperms) Companion cells Phloem fibres/Bast fibres Phloem parenchyma Sieve cells/sieve tube element are living and thin walled. Mature sieve tube elements are enucleated living cells. Central vacuole is present in each sieve cells/sieve tube element and around the central vacuole thin layer of cytoplasm is present.
