Unit 07 · The Fetal Pig
The fetal pig is the most complex specimen in the course, and the closest to human anatomy — a mammal whose organ systems are arranged much like our own. You work through it in layers, opening skin, then muscle, then the body cavity in sequence without destroying what lies beneath, and you use directional terms to say exactly where each structure sits. The work is technique and careful observation: patient, layered cuts, looking before you disturb anything, then naming each system and explaining how it mirrors ours. An instructor watches you work, and the specimen — opened cleanly, structures intact — is the proof.
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Instrument handling & safe technique | Grips the scalpel, scissors, forceps, or probe awkwardly; cuts too hard or too deep into the large specimen; puts hands or specimen at risk. | Holds the instruments correctly with reminders and cuts more carefully, but still presses too hard or steadies the specimen poorly. | Holds each instrument the right way and makes shallow, controlled cuts on a large, multi-layer specimen, working safely for both the student and the specimen. |
| Careful, layered exposure & observation | Cuts straight through skin, muscle, and organs at once, destroying deeper structures. | Opens the layers in roughly the right order but rushes and disturbs structures before observing them. | Opens skin, then muscle, then the body cavity in sequence — exposing each layer cleanly without destroying what lies beneath, and observing before disturbing anything. |
| Locating & naming external structures & orientation | Cannot point to the umbilical cord or mammary papillae, or use directional terms. | Finds a few external landmarks with prompting but confuses the anatomical planes or directional terms. | Locates and names the umbilical cord, mammary papillae, and external anatomy, and uses anatomical planes and directional terms to describe where structures sit. |
| Locating & naming internal organ systems | Guesses at the organs or names the wrong ones once the cavity is open. | Finds the larger organs but cannot reliably trace the great vessels or distinguish the small from the large intestine. | Locates and names the heart and great vessels, lungs, diaphragm, liver, stomach, small and large intestine, kidneys, and reproductive organs on the specimen. |
| Explaining structure & function (and mammalian homology & specimen care) | Cannot say what a structure does, and lets the specimen dry out or handles it carelessly or disrespectfully. | Explains one or two structures' functions but not how the pig mirrors human anatomy, and keeps the specimen moist only when reminded. | Explains why key structures do their jobs — the four-chambered heart, the diaphragm dividing the cavity, the pig serving as an analog for human anatomy — while keeping the specimen moist, handling it respectfully, and cleaning up afterward. |
| Integration (cross-domain) | Treats the science as isolated facts; makes no cross-domain connection. | Names a link to history, reading, or writing but cannot defend why it matters. | Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters. |
“I opened the skin first, then reflected the muscle, then the body wall, so the organs underneath stayed intact. This muscular sheet is the diaphragm — it separates the chest from the abdomen and drives breathing. The heart here has four chambers, just like ours, which is why the pig is such a good stand-in for human anatomy.”
“I cut straight down through everything at once, so some of the organs underneath got sliced. I’m not sure which vessel goes where, and I don’t know the words for top and bottom.”
You demonstrate this unit by doing the dissection while an instructor watches — opening the specimen in layers and locating and naming real organ systems while explaining how they mirror human anatomy, not a written test. A criterion counts as mastered only when you can perform the technique cleanly and identify and explain the structures on the actual specimen. Mastery is demonstrated, not awarded.
A 5-page clipboard packet — unit overview, key terms, the mastery rubric, anchor examples, and a score sheet you can print and grade against.