Ch 1Asexual And Sexual Reproduction In Plants — Class 12 Botany, concept-first.

Reproduction is one of the essential features of every living thing, and in plants it does far more than secure the species' own survival.

Asexual reproduction is defined as the mode of reproduction that helps an organism perpetuate its own species without any involvement of gametes.

Vegetative reproduction is a form of asexual reproduction in which a bud grows and develops into a complete new plant, without any gamete formation or fusion.

Natural vegetative reproduction takes place through adventitious buds that develop directly on a parent plant's root, stem or leaf; once these buds detach they grow into independent, genetically ident…

Beyond the naturally occurring methods, agriculture and horticulture use a range of deliberate, human-assisted propagation techniques.

Sexual reproduction is built around two linked processes: gametogenesis, the production of male and female gametes, and fertilization, their fusion.

Pre-fertilization events begin well before a flower opens, with hormonal and structural changes in the growing shoot that differentiate a floral primordium and drive it to mature into a complete flowe…

Each stamen of the androecium is made up of an anther and a filament; the anther is the business end, since it bears the pollen grains that represent the male gametophyte.

The gynoecium is the collective term for one or more pistils of a flower, each pistil (derived from a single carpel) being made up of an ovary (the basal, swollen part containing the ovules on its int…

Pollination is defined as the transfer of pollen grains from the anther to the stigma of a flower, and it is a characteristic feature of the spermatophytes (gymnosperms and angiosperms).

Fertilization is the act of fusion of male and female gametes; in angiosperms it takes the unique form of double fertilization.

Double fertilization is the phenomenon, discovered independently by S.G. Nawaschin and L. Guignard in Lilium and Fritillaria (1898-99) and unique to angiosperms, in which both male gametes carried by…

The events that occur after fertilization - development of the endosperm and embryo, and the formation of seed and fruit - are collectively called post-fertilization changes.

Reproduction that genuinely involves fertilization in flowering plants is called amphimixis; wherever reproduction happens without any union of male and female gametes, it is instead called apomixis -…

Polyembryony is defined as the occurrence of more than one embryo within a single seed, and its first documented case - in certain oranges - was reported by Anton van Leeuwenhoek as far back as 1719.

As already established, normal post-fertilization development turns the ovary into a fruit and the ovule into a seed; in a number of cases, however, a fruit-like structure develops from the ovary with…

This Evaluation section is printed by the textbook as one continuous, sequentially numbered exercise rather than separate MCQ and descriptive blocks.

Sample papers and previous-year board questions for this subject.