Biological influences - Mental health, health conditions such as cystic fibrosis, obesity, aggression, impulsiveness
Genetics - Metabolism, gender, sexual orientation, skills such as being good at drawing, genetic disorders e.g., Down's syndrome
Inherited characteristics - Eye colour, left handedness, neuroticism, extrovert, conscientiousness, agreeableness, openness
Hormones - Growth hormones, hormonal conditions such as hyperthyroidism/hypothyroidism