The cells of the quiescent centre are characterised by :
- Having light cytoplasm and small nuclei
- Dividing regularly to add to tunica
- Having dense cytoplasm and prominent nuclei
- Dividing regularly to add to the corpus
Answer
(1) Having light cytoplasm and small nuclei
Solution
The quiescent centre is a group of cells in the root apical meristem (between the root cap and the actively dividing initials) which divide very rarely.
∵ They are mitotically inactive, their cells have light (less dense) cytoplasm, small nuclei and low rates of DNA, RNA and protein synthesis.
Tunica and corpus belong to the shoot apex, not to the root, so options (2) and (4) do not apply; dense cytoplasm with prominent nuclei is the feature of actively dividing meristematic cells.
∴ Quiescent centre cells have light cytoplasm and small nuclei.
Answer: (1)