Class name Subject Book title Chapter number Content Created at
Class XII Biology Biology 1 formation of megaspores from the megaspore mother cell is called megasporogenesis. Ovules generally differentiateasinglemegasporemothercell(MMC)int...
Class XII Biology Biology 1 central cell. There is a characteristic distribution of the cells within the embryo sac. Three cells are grouped together at the micropylar end and...
Class XII Biology Biology 1 types of flowers – chasmogamous flowers which are similar to flowers of other species with exposed anthers andstigma,andcleistogamousflowers which ...
Class XII Biology Biology 1 pollen grains. Windpollinated flowers often have a single ovule in each ovary and numerous flowers packed into aninflorescence;afamiliarexampleisth...
Class XII Biology Biology 11 We are mostly obliged to estimate population sizes indirectly,withoutactuallycountingthemorseeingthem.Thetigercensus in our national parks and tige...
Class XII Biology Biology 1 a mucilaginous covering. Both wind and water pollinated flowers are not very colourful and do not produce nectar. What would be the reason for this...
Class XII Biology Biology 1 UMAN REPRODUCTION plant – cannot complete their life cycles without each other. The moth deposits its eggs in the locule of the ovary and the flowe...
Class XII Biology Biology 1 of the same plant) from fertilising the ovules by inhibiting pollen germination or pollen tube growth in the pistil. Another device to prevent self...
Class XII Biology Biology 1 those of the pistil. It is only in recent years that botanists have been able to identify some of the pollen and pistil components and the interact...
Class XII Biotechnology Biotechnology 12 spheroids. 6. What are nanomaterials? 7. Are there specific health risks from nano products? 8. Organoids can be created from: (a) Both Totipotent ...
Class XII Biology Biology 1 species and often genera to combine desirable characters to produce commercially ‘superior’ varieties. Artificial hybridisation is one of the major...
Class XII Biology Biology 1 fusion becomes the primary endosperm cell (PEC) and develops into the endosperm while the zygote develops into an embryo. (a) (b) Figure 1.13 (a) F...
Class XII Biology Biology 1 of endosperm is formed. This is an adaptation to provide assured nutrition to the developing embryo. Though the seeds differ greatly, the early sta...
Class XII Biology Biology 1 of the embryo are simple structures, generally thick and swollen due to storage of food reserves (as in legumes). Mature seeds may be non-albuminou...
Class XII Biology Biology 4 of chromosomes was parallel to the behaviour of genes and used chromosome movement (Figure 4.8) to explain Mendel’s laws (Table 4.3). Recallthatyou...
Class XII Biology Biology 1 ovary and are called true fruits. Although in most of the species, fruits are the results of fertilisation, there are a few species Reprint 2026-27...
Class XII Biology Biology 1 viable seed is of the date palm, Phoenix dactylifera discovered during the archeological excavation at King Herod’s palace near the Dead Sea. After...
Class XII Biology Biology 1 into the embryo sac and develop into the embryos. In such species each ovule contains many embryos. Occurrence of more than one embryo in a seed is...
Class XII Biology Biology 1 of the microsporangium, undergo meiosis (microsporogenesis) to form tetrads of microspores. Individual microspores mature into pollen grains. Polle...
Class XII Biology Biology 12 sharp decrease in biomass at higher trophic levels Figure 12.4 (c) Inverted pyramid of biomass-small standing crop of phytoplankton supports large ...
Class XII Biology Biology 1 of these fusions are the diploid zygote and the triploid primary endosperm nucleus (in the primary endosperm cell). Zygote develops into the embryo...
Class XII Biology Biology 1 11. What is triple fusion? Where and how does it take place? Name the nuclei involved in triple fusion. 12. Why do you think the zygote is dormant ...
Class XII Biology Biology 10 CHAPTER 10 BIOTECHNOLOGY AND ITS APPLICATIONS 10.1 Biotechnological Applications in Biotechnology, as you would have learnt from the Agriculture pr...
Class XII Biology Biology 10 from explants, i.e., any part of a plant taken out and grown in a test tube, under sterile conditions in special nutrient media. This capacity to g...
Class XII Biology Biology 10 The disorder is caused due to the deletion of the gene for adenosine deaminase. In some children ADA deficiency can be cured by bone marrow transpl...