MODEL PAPER 1 — BIOLOGY STD 11 Science — Question

Monocot Leaf
Symmetry: Isobilateral
Stomata distribution: Amphistomatic i.e., stomata equally distributed on both the surfaces.
Bulliform cells: Present on upper epidermis.
Mesophyll: Only spongy parenchyma is present which has very small intercellular spaces.
Bundle sheath: Made of parenchyma but just above and below the vascular bundles are found sclerenchymatous cells (upto epidermis)
Dicot Leaf
Symmetry: Dorsiventral
Stomata distribution: Hypostomatic i.e., stomata present on lower surface of leaf.
Bulliform cells: Usually absent.
Mesophyll: Made up of two types of tissues: Palisade parenchyma and spongy parenchyma with large intercellular spaces. Bundle sheath: Made up of parenchyma. Just above and below the vascular bundle some parenchymatous cells or collenchymatous cells are present up to epidermis.