Plant Kingdom – Angiosperms: NEET MCQs with Answers

Explanation: Double fertilisation is unique to angiosperms. One male gamete fuses with the egg to form the diploid zygote (syngamy) and the second fuses with the two polar nuclei to form the triploid primary endosperm nucleus (triple fusion).

Explanation: Microsporogenesis in the anther and megasporogenesis in the ovule are both meiotic events — the diploid microspore and megaspore mother cells divide by meiosis to give haploid microspores and megaspores respectively.

Explanation: The mature male gametophyte (germinated pollen grain) consists of a vegetative or tube cell and two male gametes (sperms) formed by the mitotic division of the generative cell. Both sperms are used in double fertilisation.

Explanation: Double fertilisation, in which one male gamete fuses with the egg and the other with the two polar nuclei, is universal among angiosperms and is found nowhere else. The other characters all have exceptions — monocots generally lack normal secondary growth, vessels are absent in a few primitive families such as Winteraceae, and total parasites such as Cuscuta and Rafflesia are not autotrophic.

Explanation: The angiosperms owe their success to an exceptional adaptive range: the flower with its many devices for animal pollination, the closed carpel protecting the ovules, double fertilisation with an efficient nutritive endosperm, fruits that aid dispersal, vessels for rapid conduction and a great variety of growth forms from herbs to trees. Together these have enabled them to colonise almost every terrestrial habitat.

Explanation: The megasporangium corresponds to the ovule.

Explanation: In angiosperms, the entire OVULE corresponds to the megasporangium (containing the nucellus + integument + female gametophyte).

Explanation: Solanaceae (for example Solanum) has a bicarpellary syncarpous ovary with an obliquely placed septum (NEET 2019 key). Brassica has a transversely placed false septum (replum).

Explanation: Wind-pollinated flowers often have a single ovule in each ovary and are packed into inflorescences, as in corn cobs and grasses (NEET 2017 key).

Explanation: In free-central placentation the ovules sit on a central axis with no septa, as in Dianthus and Primrose. Citrus is axile, and Argemone and Brassica are parietal.

Explanation: Brassica (mustard) has actinomorphic (radially symmetrical) flowers. Trifolium, Pisum and Cassia are legumes with zygomorphic flowers.

Explanation: Stamens of unequal length occur in Salvia (didynamous) and in mustard, radish and turnip (tetradynamous, Brassicaceae), so the count is four (NEET 2016 key).

Explanation: Polyadelphous describes stamens whose filaments are united into more than two bundles, as in citrus, so it refers to the androecium.

Explanation: Lemon (Citrus) has axile placentation: ovules on a central axis of a multilocular ovary. Pea has marginal, Argemone parietal and Dianthus free-central placentation.

Explanation: Cucumber (Cucurbitaceae) has separate staminate and pistillate flowers, so its flowers are unisexual. China rose, onion and pea have bisexual flowers.