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: The development of apomorphine - induced ( 1 . 0 mg / kg s . c . once daily ) aggressive behavior of adult male and female Wistar rats obtained from the same breeder was studied in two consecutive sets .
### Output Text:
The development of <span class="chemical">apomorphine</span> - induced ( 1 . 0 mg / kg s . c . once daily ) aggressive behavior of adult male and female Wistar rats obtained from the same breeder was studied in two consecutive sets . 