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Magazine Problem 227
Assertion: Embryos of monocotyledons posses only one cotyledon. Reason: In the grass family the cotyledon is called scutellum.
Problem 228
Assertion: Parthenocarpic fruits are seedless Reason: Parthenocarpic fruits develop without fertilization.
Problem 229
Assertion: Angiosperm can colonize is other areas easily. Reason: Angiosperms have seeds and seeds have better adoptive strategies for dispersal to new habitats.
Problem 232
Assertion: Exine of pollen grain is discontinuous layer. Reason: Exine absent at germ pores.
Problem 233
Assertion: Pollen grains of some species can cause asthma. Reason: Pollen grains of some species are act as allergens.
Problem 234
Assertion: Pollen bank can be formed for crop breeding programmes. Reason: Pollen grain of many species can be stored for year in liquid nitrogen \(\left(-196^{\circ} \mathrm{C}\right)\)
Problem 235
Assertion: Wind pollinated plant have large feathery stigma. Reason: Feathery stigma easily traps air-borne pollen grains.
Problem 236
Assertion: Water pollinated species have mucilaginous covering on pollen grains. Reason: Mucilage covering protect pollen grain from wetting.
Problem 237
Assertion: Majority of flowering plant have bisexual flower still they show cross pollination. Reason: Continued self-pollination results in inbreeding depression.
Problem 238
Assertion: Self incompatibility is genetic mechanism to prevent self pollination. Reason: It promotes germination of pollen from same plant or same flower on stigma.
