Students investigate the external and internal anatomy of a rat to learn how mammalian organ systems are structured and interconnected. The rat serves as a representative model for mammalian anatomy and physiology.

• Follow instructions provided in the links below.

Rat Dissection || When the Cat's Away [EDU] - Silvergrass Institute:

Rat dissection at the Department of Zoology, University of Johannesburg - University of Johannesburg YouTube Channel:

📄 Mammal (Rat) Dissection - LibreTexts Biology: https://bio.libretexts.org/Courses/Northeast_Wisconsin_Technical_College/General_Biology_Laboratory_Manual/Laboratory_14%3A_Vertebrates/14.03%3A_Mammal_(Rat)_Dissection

📄Virtual Rat Dissection - Biology Corner: https://www.biologycorner.com/worksheets/rat_dissection.html

• Compare the rat’s anatomy with that of other vertebrates such as frogs or fetal pigs.
• Create labeled diagrams of each organ system.
• Perform a functional comparison between rat organ systems and human anatomy.

• Wear gloves and a lab coat throughout the dissection.
• Handle scalpels and scissors carefully to avoid injury.
• Respect the specimen as it was once a living animal.
• Dispose of specimens and waste materials according to lab protocols.
• Clean and disinfect all tools, trays, and surfaces after use.
• Wash hands thoroughly at the end of the lab.

• How does the skin of a frog differ from the skin of a rat? (Frogs have permeable, moist skin for respiration, while rats have fur-covered skin for insulation and protection.)
• Frogs and rats are both vertebrates. What does this tell you about their evolutionary relationship? (They share a common ancestor and have homologous structures despite differences.)
• How do the limbs of a frog compare to those of a rat? (Frogs have long hind limbs adapted for jumping, while rats have limbs adapted for running and climbing.)
• Why is a four-chambered heart more efficient than a three-chambered heart? (It completely separates oxygenated and deoxygenated blood, improving oxygen delivery.)
• How do mammalian lungs differ from amphibian lungs? (Mammalian lungs have greater surface area and complexity for higher oxygen demand.)
• How does the rat’s digestive tract reflect its diet compared to a frog’s? (The rat’s longer, more complex digestive tract supports a varied omnivorous diet.)
• What are three homologous structures in the frog and rat? (Examples: vertebral column, forelimbs, heart chambers—showing shared ancestry.)
• What adaptations allow the frog to live an amphibious lifestyle? (Moist skin for gas exchange, strong hind limbs for swimming and jumping.)
• What adaptations make the rat suited to terrestrial life? (Fur for insulation, efficient lungs, four-chambered heart.)
• What are some unique characteristics of mammals? (Hair/fur, mammary glands, live birth in most species, four-chambered heart.)