In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: Prenatal protein deprivation alters dopamine - mediated behaviors and dopaminergic and glutamatergic receptor binding .
### Output Text:
Prenatal protein deprivation alters <span class="chemical">dopamine</span> - mediated behaviors and dopaminergic and glutamatergic receptor binding . 