Genetic inheritance – IB Psychology Study Notes

Comprehensive IB Psychology study notes on Genetic inheritance. Covers key theories, research studies, and evaluation points for the 2027 syllabus.

Mark Scheme SECTION A MARK SCHEME 4 marks Must Include: • Genotypes passed from parents to offspring • Biological predisposition concept • Concordance rates: MZ vs DZ comparison • Higher MZ concordance = stronger genetic component • Named condition e.g. major depressive disorder • Gene example e.g. 5-HTT serotonin transporter • Non-100% concordance = environmental factors also necessary Link Formula: "Higher MZ than DZ concordance indicates genetic influence, but non-100% concordance shows envir...