Biology
Sexual Reproduction in Flowering Plants
पुष्पी पादपों में लैंगिक जनन
This Class 12 Biology chapter explains how flowering plants reproduce sexually, from the formation of male and female gametophytes to pollination, pollen–pistil interaction, fertilisation, and the development of seeds and fruits. Students explore the structure and function of flowers, double fertilisation, embryo and endosperm formation, and special processes such as apomixis, polyembryony, and parthenocarpy. The chapter also connects reproduction with plant life cycles, genetic variation, and the biological importance of seed formation.
1Flower structure and development
पुष्प की संरचना एवं विकास
In Class 12 Biology, this topic from Chapter 1, “Sexual Reproduction in Flowering Plants,” explains how a flower is organized and how it develops as the reproductive structure of an angiosperm. Students study the calyx, corolla, androecium, and gynoecium, along with the roles of anther, pollen grain, stigma, style, and ovary. They also connect flower development with microsporogenesis, megasporogenesis, formation of male and female gametophytes, pollination, and the conditions that lead to fertilization and seed formation.
2 questionsMicrosporogenesis and Megasporogenesis
लघुबीजाणुजनन और गुरुबीजाणुजनन
In Class 12 Biology, this topic from Chapter 1, Sexual Reproduction in Flowering Plants, explains how male and female spores form in flowering plants. Students learn how sporogenous tissue develops into pollen mother cells and undergoes meiosis to produce microspore tetrads, while megaspore mother cells divide to form megaspores, usually leaving one functional megaspore. The topic connects these processes with pollen grain formation and the development of the embryo sac.
1 questionsPollination types, agencies, and examples
परागण के प्रकार, माध्यम और उदाहरण
In Class 12 Biology, Chapter 1, “Sexual Reproduction in Flowering Plants,” this topic explains pollination as the transfer of pollen from anther to stigma. Students distinguish autogamy, geitonogamy and xenogamy, compare self- and cross-pollination, and study abiotic agencies such as wind and water and biotic agencies including insects, birds and bats. Familiar examples and floral adaptations show how each agency supports pollen transfer and affects reproduction in flowering plants.
0 questionsOutbreeding devices and pollen-pistil interaction
पर-प्रजनन युक्तियाँ और परागकण–स्त्रीकेसर अंतःक्रिया
In Class 12 Biology, this topic from Chapter 1, Sexual Reproduction in Flowering Plants, explains how flowering plants reduce self-pollination and promote cross-pollination through outbreeding devices such as dichogamy, herkogamy, self-incompatibility and unisexuality. It also explores pollen–pistil interaction, including pollen recognition, compatibility, pollen germination and pollen tube growth, showing how the pistil guides and regulates successful fertilisation.
1 questionsDouble fertilization
द्वि-निषेचन
In Class 12 Biology, this topic from Chapter 1, “Sexual Reproduction in Flowering Plants,” explains the distinctive fertilisation process in angiosperms. Students learn how the pollen tube delivers two male gametes to the embryo sac: one fuses with the egg to form the diploid zygote (syngamy), while the other fuses with the two polar nuclei to produce the triploid primary endosperm nucleus (triple fusion). The topic also connects double fertilization with embryo and endosperm development and seed formation.
2 questionsPost-fertilization events
निषेचन के बाद की घटनाएँ
In Class 12 Biology, this topic from Chapter 1, Sexual Reproduction in Flowering Plants, explains the changes that follow fertilisation in an angiosperm. Students learn how the zygote develops into an embryo, how the primary endosperm nucleus gives rise to endosperm, and how the ovule matures into a seed with protective coverings. It also covers the transformation of the ovary into a fruit, formation of the pericarp, seed maturation, dormancy and the basic link between these processes and successful germination.
0 questionsDevelopment of seed and formation of fruit
बीज का विकास और फल का निर्माण
In Class 12 Biology, this topic from Chapter 1, “Sexual Reproduction in Flowering Plants,” explains how a fertilised ovule develops into a seed and how the ovary matures into a fruit. Students learn about embryo formation, endosperm development, seed coat formation, and the transformation of the ovary wall into the pericarp. The topic also connects fertilisation with seed maturation, fruit structure, and the role of seeds and fruits in protecting the embryo and supporting plant reproduction.
4 questionsSpecial modes: Apomixis, Parthenocarpy, Polyembryony
विशेष प्रजनन विधियाँ: एपोमिक्सिस, पार्थेनोकार्पी और बहुभ्रूणता
In Class 12 Biology, this topic extends the study of sexual reproduction in flowering plants by introducing three special reproductive phenomena. Students learn how apomixis produces seeds without fertilisation, how parthenocarpy leads to fruit development without fertilisation and often results in seedless fruits, and how polyembryony results in more than one embryo developing within a single seed. The topic also helps connect these processes with plant propagation, fruit production, and their significance in agriculture.
0 questions