Across
- 3. A neurotransmitter thought to be involved in OCD and depression
- 7. The actual makeup of someone's genes
- 9. Term for identical twins
Down
- 1. Behaviour is influenced by innate, biological factors
- 2. Physical structure of the brain
- 4. Behaviour is influenced by environmental factors
- 5. Term for non-identical twins
- 6. The way genes interact with the environment
- 8. A neurotransmitter thought to be involved in addiction