31 Years NEET Previous Year Questions: Sexual Reproduction in Flowering

Filiform apparatus helps in the entry of pollen tube into a synergid in ovule. Filiform apparatus is in form of finger like projection comprising a core of micro fibrils enclosed in a sheath. The filiform apparatus resembles transfer cells" meant for short distance movement of metabolites. The filiform apparatus responsible for the absorption of food from the nucleus.
Topic in NCERT: Pollen-pistil interaction
Line in NCERT: "Many recent studies have shown that filiform apparatus present at the micropylar part of the synergids guides the entry of pollen tube."

Unisexuality of flowers prevents. autogamy, but not geitonogamy. In self fertilisation , the male and female gametes are derived from the same individual. Among plants, self fertilization also called autogamy is common in many cultivated species, eg., wheat and oats. However, self fertilization is a form of inbreeding and does not allow for the mixing of genetic material; if it occurs over a number of generations it will result in offspring being less vigorous and productive than those resulting from cross fertilization.
Topic in NCERT: Self-Pollination and Its Prevention
Line in NCERT: "Another device to prevent self-pollination is the production of unisexual flowers. If both male and female flowers are present on the same plant such as castor and maize (monoecious), it prevents autogamy but not geitonogamy."

In pea, endosperm is consumed by developing embryo in the seed. The endosperm is completely absorbed by the growing embryo and the food reserve gets stored in the cotyledons. Such seeds are called non endospermic or exalbuminous.
Topic in NCERT: Endosperm
Line in NCERT: "Endosperm may either be completely consumed by the developing embryo (e.g., pea, groundnut, beans) before seed maturation or it may persist in the mature seed (e.g. castor and coconut) and be used up during seed germination."

The egg cell is one of the haploid cell of egg apparatus present in the micropylar end of embryo sac in seeded plants. It is also cal led oosphere and represents the single female gamete of the embryo sac. Antipodal cells are the haploid cells, usually three in number, present in embryo sac at the opposite end of micropyle. Their function is unknown and at fertilization, they may disintegrate or multiply and enlarge.

Generative cell which is a  cell of the male gametophyte or pollen grain in seed plants that divides to give rise directly or indirectly two sperms.
Topic in NCERT: Pollen Development and Structure
Line in NCERT: "The generative cell divides mitotically to give rise to the two male gametes before pollen grains are shed (3-celled stage)."

In a dicot plant general arrangement of nuclei in the embryosac is that 3 nuclei in 3 cells of egg apparatus (one egg cell & 2 synergids) at micropylar end and 2 polar nuclei in almost middle region and 3 nuclei in the form of antipodals at the distal end from micropyle, towards nucellus. So total nuclei 3 + 2 + 3.
Topic in NCERT: Embryo Sac Development
Line in NCERT: "Three cells are grouped together at the micropylar end and constitute the egg apparatus. The egg apparatus, in turn, consists of two synergids and one egg cell. The large central cell, as mentioned earlier, has two polar nuclei. Thus, a typical angiosperm embryo sac, at maturity, though 8-nucleate is 7-celled."

In flowering plants, archesporium cells undergo periclinal (transverse) division to form outer primary parietal layer and inner sporogenous cells. Primary parietal wall after few more periclinal divisions form anther wall and sporogenous cells give rise to sporogenous tissue.
Topic in NCERT: Summary
Line in NCERT: he central tissue is the nucellus in which the archesporium differentiates. A cell of the archesporium, the megaspore mother cell divides meiotically and one of the megaspores forms the embryo sac (the female gametophyte).