The Milliy sertifikat (National Certificate) Biology exam has calculation problems as well as theory: on DNA, genetics and populations. These problems rest on a few rules, and once you know them the open part becomes a good source of points.
Exam structure
In the official sample: 1-35 are closed test questions (1.3 and 2.2 points) and 36-45 are open tasks (a) 1.5 + b) 1.7 points). 100 raw points in total, 150 minutes.
Key rules for the problems
- Complementarity: A = T (2 hydrogen bonds), G = C (3 hydrogen bonds); A + G = T + C = 50 %.
- The distance between neighbouring nucleotides is 0.34 nm, so the fragment length gives you the number of pairs.
- Each amino acid is coded by a codon of 3 nucleotides.
- Hardy-Weinberg: p + q = 1 and p² + 2pq + q² = 1; the share of individuals with the recessive trait equals q².
- In a dihybrid cross (AaBb × AaBb) the phenotype ratio is 9 : 3 : 3 : 1.
Theory topics
- Cell structure and the functions of organelles.
- Stages of mitosis and meiosis.
- Photosynthesis and energy metabolism (glycolysis, the Krebs cycle).
- Human physiology: circulation, breathing, digestion, the nervous system.
- Evolution and ecology.
