Question

Read the following statements:
I. Sieve cells and albuminous cells originate from single mother cell.
II. Treachery elements have perforated end walls with wider lumen.
III. Sieve tube elements are found in plants like Cycas and Pinus.
IV. Callose is deposited around sieve pores on sieve plates.
Of these, the correct statements are,

• A. I and III
• B. II and IV
• C. I, II, III
• D. I, II, IV

Answer 1

Answer: (B)

Vascular Tissues like xylem (Water conduction) and Phloem (Food conduction)found in pteridophytes, gymnosperms and angiosperms consist of different cell types.
The xylem is composed of Tracheids, Treachery Elements, Xylem fibers and Xylem parenchyma. The tracheids are found in pteridophytes and gymnosperms. Treachery Elements, also called xylem vessel elements are found in angiosperms.
The tracheary elements are more advanced than tracheids and possess perforated end walls with wider lumen.
In phloem, the different cell types like Sieve cells, Sieve tube elements, Companion cells, Phloem fibres and phloem parenchyma are present. Sieve cells are present in pteridophytes and gymnosperms and are associated with specialized parenchymatous cells called albuminous cells. The sieve tube elements are present in angiosperms and are associated with companion cells. The sieve tube element and a companion cell are originated from the same mother cell, where as sieve cells and albuminous cells are originated from different mother cells.
The sieve tube elements are enucleated and possess cytoplasmic streaming. They have perforated end walls or cross walls and it is called sieve plate. The sieve plates contain sieve pores. Surrounding the sieve pores, a plant polysaccharide called Callose is deposited. It is composed of glucose residues