Biology: Zoology and Botany Core Processes
Biology on KUUMAT combines Zoology and Botany from the NEB 10+2 syllabus: cell structure and division, genetics and molecular biology, human physiology, plant anatomy and physiology, reproduction, ecology, and basic taxonomy. Questions often test a process in sequence or ask you to interpret a cross, graph, or experimental result.
Core rules
- Cell division: mitosis keeps chromosome number; meiosis halves it and creates variation through crossing over and independent assortment.
- Genetics: use a Punnett square; a monohybrid Tt × Tt gives genotypic 1 TT : 2 Tt : 1 tt and phenotypic 3 tall : 1 dwarf.
- Photosynthesis: light reactions split water, release O₂, and make ATP/NADPH; the Calvin cycle fixes CO₂ using RuBisCO.
- Human physiology: follow the pathway-e.g., blood flows right atrium → right ventricle → lungs → left atrium → left ventricle → aorta.
- Ecology: energy flows one way and is lost at each trophic level; nutrients cycle.
Worked example
Two heterozygous tall pea plants (Tt) are crossed. Each parent makes T and t gametes in equal proportion. Punnett square: TT, Tt, Tt, tt. Genotypic ratio 1:2:1; phenotypic ratio 3 tall : 1 dwarf. Probability of a tall offspring is 3/4; probability of a homozygous tall offspring is 1/4.
Traps
- Confusing mitosis and meiosis II: both separate sister chromatids, but meiosis II follows meiosis I.
- Mixing template and coding strands in transcription.
- Saying stomata open at night in CAM plants but forgetting the timing of CO₂ fixation.
- Swapping xylem and phloem functions; xylem transports water/minerals upward, phloem transports sugars.
- Treating “dominant” as “more common.”