http://www.mhhe.com/biosci/genbio/virtual_labs/BL_16/BL_16.html
Go through the:
INTRODUCTION
Why Dissect
Natural History
Dissection Tool
EXTERNAL ANATOMY
Orientation
Skin
Head
Cloaca
Legs
INTERNAL ANATOMY
Initial Cut
Digestive System
Respiratory System
Circulatory System
Reproductive System
Excretory System
Nervous System
Muscular System
Skeletal System