Botany and Plant Science

Tunic is a membranous protective covering over the bulb.

It has axillary bud tendrils.

The leaves are either highly reduced or modified into spines.

Wheat and other grasses (monocots) have dumb-bell shaped guard cells, while dicots like beans, groundnut, and sunflower have kidney-shaped guard cells. This structural difference is a key anatomical feature distinguishing monocots from dicots in their leaf anatomy.

The male gametophyte in angiosperms (pollen grain) is highly reduced and shows precocious development - it is mature and ready for germination at anthesis (flower opening), unlike in gymnosperms where gametophyte development continues after pollination. In Pinus, the female gametophyte develops slowly over months, while fern prothallus is an independent free-living gametophyte without precocious development.

In Antigonon leptopus (coral vine), the reproductive structures (inflorescences) are modified into climbing tendrils that help the plant attach to and climb along supports. Clematis uses leaf petioles modified into tendrils, grape-vine uses stem tendrils, and agave does not have modified reproductive structures for climbing. Note: The option spelling 'antignon' appears to be a typo for 'antigonon'.

The angiosperm embryo sac (female gametophyte) and the fern prothallus are homologous structures because both represent the gametophyte generation in their respective plant life cycles. Both are haploid, produce eggs, and are the free-living or independent phase (though in angiosperms, the embryo sac is embedded within sporophyte tissue). The nucellus in Pinus is sporophyte tissue (part of the ovule), and the sporogonium of Funaria is the sporophyte generation.

In monocot roots, the pericycle (a layer of cells beneath the endodermis) is responsible for initiating lateral root primordia. Unlike dicot roots, monocot roots typically lack vascular cambium and do not undergo secondary growth (they have no secondary thickening). Option A is incorrect because cork arises from cork cambium in the cortex, not pericycle. Option B is incorrect because vascular cambium is absent in monocot roots. Option D is incorrect because monocot roots do not show secondary growth.

Diadelphous androecium is characterized by stamens whose filaments are fused into two separate bundles (groups), while anthers remain free. The number of filaments in each bundle can vary - in Fabaceae (pea family), the typical arrangement is 9+1 (nine stamens in one bundle, one stamen separate). Option A is incorrect because simply being in two groups is not sufficient - fusion must occur. Option B is incorrect because complete fusion (including anthers) would make it synandrous, not diadelphous. Option D is incorrect because the number of filaments is not fixed - it varies among species.

Solenostele is a type of siphonostele found in ferns and other plants with megaphyllous leaves (large, complex leaves with branched veins). It differs from the protostele of plants with microphyllous leaves like Selaginella.

Apospory is a process in which diploid embryo sac directly develops from an ordinary diploid saprophyte cell.

This process is called parthenocarpy.

In ferns, sporangia are found on the abaxial surface.

The male gametes of lower plants are called spermatozoids.

The development of embryo from any cell of the gametophyte, other than the egg cell, is called apogamy.