Which one of the following statements is correct?
- (a)Xylem consists of tracheids, vessels, xylem parenchyma and xylem fibres.
- (b)Flexibility in plants is due to sclerenchyma.
- (c)Parenchyma have no intercellular spaces.
- (d)Xylem consists of sieve plate, sieve tube and companion cells.
Correct — A, xylem consists of tracheids, vessels, xylem parenchyma and xylem fibres. Xylem is a complex conducting tissue, and statement (a) lists its four elements correctly. It carries water and dissolved minerals upward from the roots and also gives the plant mechanical support.
- (b)Flexibility in plants is due to sclerenchyma. — Flexibility is provided by collenchyma (cells with thickened corners); sclerenchyma gives rigidity and mechanical hardness, not flexibility.
- (c)Parenchyma have no intercellular spaces. — Parenchyma cells usually have prominent intercellular spaces; the statement is the opposite of the truth.
- (d)Xylem consists of sieve plate, sieve tube and companion cells. — Sieve tubes, sieve plates and companion cells are the components of phloem, not xylem.
Plant tissues are simple (parenchyma, collenchyma, sclerenchyma) or complex (xylem and phloem). Xylem conducts water and minerals and is made of tracheids, vessels, xylem parenchyma and xylem fibres; phloem conducts food and is made of sieve tubes, sieve plates, companion cells, phloem parenchyma and phloem fibres.
The item mixes true and false claims about these tissues. Knowing the exact components of xylem versus phloem, and the roles of collenchyma (flexibility) and sclerenchyma (rigidity), lets you keep only statement (a).
- Xylem elements: tracheids, vessels (tracheae), xylem parenchyma and xylem fibres.
- Xylem conducts water and minerals upward and gives mechanical support.
- Phloem contains sieve tubes, sieve plates, companion cells, phloem parenchyma and phloem fibres.
- Among simple tissues, collenchyma provides flexibility while sclerenchyma provides rigidity.
- Swapping xylem and phloem components — sieve tubes and companion cells belong to phloem.
- Mixing up collenchyma (flexibility) with sclerenchyma (rigidity).
Asked as a 'which statement is correct' item that mixes xylem and phloem components with the roles of collenchyma and sclerenchyma.
No directly related past PYQ was found.
- practice — not a real PYQ
Which one of the following is a component of phloem?
- (a)Tracheid
- (b)Vessel
- (c)Companion cell
- (d)Xylem fibre
Answer(c) Companion cell — sieve tubes and companion cells make up phloem, not xylem.
- practice — not a real PYQ
Flexibility in young plant parts is chiefly provided by
- (a)sclerenchyma
- (b)collenchyma
- (c)xylem
- (d)cork
Answer(b) collenchyma — its unevenly thickened walls give flexibility.