Biology Formula Sheet
5 formulas across 3 chapters — with variables explained and exam tips where needed.
Ch 1Reproduction in Organisms(1 formulas)
Lifecycle length
Juvenile phase + Reproductive phase + Senescent phase = Lifespan
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Not a formula — a conceptual relationship tested as assertion-reason
Ch 6Molecular Basis of Inheritance(3 formulas)
Chargaff's Rule
A = T | G = C | A+G = T+C (Purines = Pyrimidines)
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Most important equation in genetics — appears every year
DNA base percentage
If A% is given: T = A%, G = C = (100 − 2A)/2 %
Number of H-bonds in DNA
H-bonds = 2×(A=T pairs) + 3×(G≡C pairs)
Ch 7Evolution(1 formulas)
Hardy-Weinberg Principle
p² + 2pq + q² = 1 and p + q = 1
p = frequency of dominant allele, q = frequency of recessive allele