Biology
The Biology domain of MP PAT tests cell structure, plant physiology, genetics, reproduction, human physiology, and ecology. Expect definition-based questions plus simple crosses, diagrams described in words, and ecosystem relationships.
Cell and plant physiology
- Prokaryotes lack a membrane-bound nucleus; eukaryotes have organelles including mitochondria and chloroplasts.
- Photosynthesis: light reaction makes ATP and NADPH; Calvin cycle fixes CO2. Respiration releases energy from glucose.
- Transpiration pulls water through xylem; stomata regulate gas exchange.
Genetics and reproduction
- Mendel’s law of segregation: alleles separate during gamete formation.
- Monohybrid cross Tt × Tt gives genotype 1 TT : 2 Tt : 1 tt and phenotype 3 tall : 1 dwarf.
- Mitosis produces identical body cells; meiosis produces four haploid gametes with variation.
Human physiology and ecology
- Know digestion, blood circulation, and breathing basics; enzymes act on specific substrates.
- Food chain: producer → primary consumer → secondary consumer; energy decreases at each trophic level.
Worked example
Cross two heterozygous tall pea plants (Tt × Tt). Each parent makes T and t gametes. The Punnett square gives TT, Tt, Tt, tt. Genotypic ratio = 1 TT : 2 Tt : 1 tt; since T is dominant, phenotypic ratio = 3 tall : 1 dwarf. The probability of a dwarf offspring is 1/4.
Traps that cost marks
- Confusing genotype with phenotype; writing 3:1 as a genotypic ratio.
- Mixing mitosis and meiosis; forgetting meiosis halves chromosome number.
- Reversing photosynthesis and respiration equations; ignoring energy loss in food chains.