A. The flowers of Vallisneria are colourful and produce nectar.
B. The flowers of water lily are not pollinated by water.
C. In most of water-pollinated species, the pollen grains are protected from wetting.
D. Pollen grains of some hydrophytes are long and ribbon like.
E. In some hydrophytes, the pollen grains are carried passively inside water.
Choose the correct answer from the options given below.
AI-generated explanation. Check against your textbook.
Explanation:
The correct set is B, C, D and E. Vallisneria (an aquatic hydrophyte) has underwater flowers and is not known for colorful flowers with nectar; water-lily flowers are typically pollinated by insects or wind and are not pollinated by water. In water-pollinated species, pollen grains are adapted to resist wetting (C). Some hydrophytes have pollen that is long and ribbon-like (D). In some hydrophytes, pollen can be carried passively within water (E). Thus A is incorrect, while B, C, D and E are correct, matching option 1.
🧠 Did You Know?
Hydrophytes often rely on water for pollination, and their pollen shows adaptations to aquatic life to avoid premature wetting and to float or move with water currents.
💡 NCERT Memory Line:
In hydrophytes, pollen/pollination adaptations include protection from wetting and water-mediated pollen movement, not reliance on insects or wind unless adapted for that method.
The type of conservation in which the threatened species are taken out from their natural habitat and placed in special setting where they can be protected and given special care is called:
AI-generated explanation. Check against your textbook.
Explanation:
Bulliform cells are large, bubble-like epidermal cells found in monocots. When they lose water, they become flaccid and cause the leaf to roll inward. This curling reduces surface area and transpiration, helping the plant conserve water during drought. So option 2 (Inward curling of leaves in monocots) is correct.
? Did You Know?
Most monocots with bulliform cells include grasses like wheat and rice, which roll their leaves to cope with water stress.
? NCERT Memory Line:
Bulliform cells help in leaf rolling under water stress in monocots.
Tropical regions show greatest level of species richness because:
A. Tropical latitudes have remained relatively undisturbed for millions of years, hence more time was available for species diversification.
B. Tropical environments are more seasonal.
C. More solar energy is available in tropics.
D. Constant environments promote niche specialization.
E. Tropical environments are constant and predictable.
Choose the correct answer from the options given below.