The unit in one line
How botany is put to work: growing whole plants from a few cells, moving genes between organisms, and feeding a country through biofertilisers, breeding and safe food. 3 of Botany's 40 questions over three chapters, with Nepal's own examples throughout.
Read in this order
- Plant tissue culture (9 min) — totipotency, the culture medium and the hormone ratio, the steps from explant to hardened plant, and the types from micropropagation to somatic hybrids.
- Genetic engineering (9 min) — restriction enzymes, ligase and vectors, the steps of making recombinant DNA, PCR in outline, and GM crops with the concerns they raise.
- Biofertilisers, breeding and food security (10 min) — nitrogen-fixing biofertilisers and green manures, the steps of plant breeding and the Green Revolution, bio-engineering, food safety and FAO's four pillars of food security.
About 30 minutes in all. Transgenic animals and applied microbiology are taught in Zoology: see the Zoology unit 7 map.
How it is asked
MEC sets the paper roughly half recall, a third understanding and a fifth application. Recall here is names and dates (Haberlandt, Borlaug), the enzyme that cuts and the enzyme that joins, and which organism fixes nitrogen with which plant. Understanding is why a meristem gives virus-free plants, or why a high cytokinin-to-auxin ratio gives shoots. Application is a described culture or cloning experiment to diagnose, or a food-security problem to place under its pillar.
Then practise
Each chapter has a fixed-length chapter test under Practice › Topics, drawn from questions written to that chapter's scope. Sit it after reading; a second sitting a week later shows whether it stuck.