Parallel venation in leaves is a characteristic feature of
- A.Dicotyledons
- B.Monocotyledons
- C.Gymnosperms
- D.Pteridophytes
Correct answer
Explanation
The correct answer is B, monocotyledons. In a monocot leaf, such as that of wheat, maize, grass, banana or canna, the veins run side by side along the length of the lamina without forming a network, and this parallel venation goes with the other monocot features: one cotyledon in the seed, a fibrous root system, scattered vascular bundles and flowers in threes. A is wrong because dicotyledons such as mustard, peepal and China rose show reticulate venation, a branching network of veins with a prominent midrib. C is wrong because gymnosperms are not flowering plants and their needle-like leaves have one or two unbranched veins. D is wrong because pteridophytes, the ferns, bear fronds with dichotomously branching veins and reproduce by spores, not seeds. A useful check in the field is that a monocot leaf is usually long and strap-shaped with a sheathing leaf base, while a dicot leaf has a distinct petiole and a broad lamina.
Read the full article: Morphology of Flowering Plants: Root, Stem and Flower
Practice Questions
View allWhich of the following plants can survive in extremely saline conditions?
- A.Epiphytes
- B.Halophytes
- C.Xerophytes
- D.Hydrophytes
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Halophytes are plants of saline soils, chiefly the mangroves of tidal creeks and deltas such as Rhizophora and Avicennia, and their morphology is shaped by that habitat: they bear pneumatophores, negatively geotropic breathing roots that rise out of the waterlogged mud, along with stilt and prop roots for support and…
Read the full explanation →The potato is a modification of which plant organ?
- A.Root
- B.Stem
- C.Leaf
- D.Fruit
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The potato is an underground stem tuber, the swollen tip of an underground branch, and the proof is in its morphology: it bears nodes, the depressions called eyes, and each eye carries an axillary bud that can sprout into a new shoot.
Read the full explanation →The edible part of the carrot is a modified
- A.Conical taproot
- B.Fibrous root
- C.Stem tuber
- D.Adventitious root
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The carrot stores food in its primary root, which is broad at the top and tapers steadily to a point, and that shape is described as conical.
Read the full explanation →Prop roots, which hang from spreading branches and give them mechanical support, are a familiar feature of which tree?
- A.Maize
- B.Banyan
- C.Screw pine
- D.Rhizophora
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The banyan's horizontal branches grow so long and heavy that they send down thick aerial roots which reach the soil, thicken into pillars and carry the weight of the branch; these are called prop or pillar roots.
Read the full explanation →Pneumatophores, the negatively geotropic breathing roots, are characteristic of
- A.Mangrove plants such as Rhizophora
- B.Desert plants such as Opuntia
- C.Epiphytic orchids such as Vanda
- D.Parasitic plants such as Cuscuta
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The mud of a tidal swamp is waterlogged and almost free of oxygen, so these plants send up roots that grow vertically out of the soil into the air and take in oxygen through pores; such roots grow against gravity and are therefore called negatively geotropic.
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