Explain the biological theories of juvenile delinquency and their modern evaluation.

The body's account of the young offender: Lombroso's atavism (the born criminal's stigmata — the founding error and the method's beginning); the heredity studies (twins and adoptions — the genetic share of aggression-and-impulsivity, modest and interactive); the neurological turn — head injury, ADHD-and-impulse disorders, the prefrontal maturation's pace (the modern biology that actually matters for juveniles: the developmental biology of 1.3, not the defect biology of Lombroso); the nutrition-and-toxin hypotheses (lead's shadow — the environmental-biology frontier); and the hormonal adolescence (puberty's activation effects). The verdict (the exam's line): biology supplies dispositions and vulnerabilities, never destinies — and for juveniles especially, the biology is in motion (the maturity gap that most grow out of).