Use these targets, vocabulary, rubrics, examples, and score sheet with the instructor's approved lesson and procedure. This is an assessment companion, not a complete lesson or safety authorization.
Student lessons, data, and public practice answers (not assessment keys): Unit 02 learning pathway.
The student demonstrates the following:
Five science criteria plus separately reported integration (Page 3).
Open the specimen and locate, name, and explain real structures — watched live.
The student explains why each structure does its job (Page 4 anchors).
Careful observations of the external and internal structures kept distinct.
Decide from evidence. Technique criteria are mastered only when an educator observes them; identification and explanation criteria can be mastered on the approved specimen, image, model, or virtual route without penalty. Each student has three tokens per term; each token retries one rubric criterion. Approved accommodations, equipment failures, and approved absences are handled separately and do not consume these tokens.
Accept listed synonyms; use the distinction column to resolve near-matches.
| Term | Accepted explanation | Distinction |
|---|---|---|
| Clitellum | saddle; band | The smooth, swollen band near the front; secretes the cocoon, not a random thickening |
| Segment | metamere; annulus | The body is built of repeated segments; count from the anterior end |
| Setae | bristles; chaetae | Tiny bristles on each segment that grip the soil; felt more than seen |
| Anterior / posterior | front / rear | The mouth end is anterior; the clitellum sits toward the front and orients the worm |
| Pharynx | throat | Muscular; pulls food in at the anterior end, ahead of the crop |
| Crop | storage sac | Thin-walled; stores food before the gizzard |
| Gizzard | grinding chamber | Thick, muscular wall grinds food; feels firm compared with the crop |
| Intestine | gut | Runs the length behind the gizzard, where food is absorbed |
| Dorsal blood vessel | main dorsal vessel | The dark line along the top side; carries blood forward |
| Aortic arches | hearts | Five pairs of muscular vessels near the front that pump blood; not one heart |
| Nephridia | excretory tubules | Paired in most segments; remove waste |
| Ventral nerve cord | nerve cord | Runs along the bottom side; dorsal vessel on top, nerve cord below |
| Segmentation | repeated body units | Useful body-plan evidence; not a rank or a step toward another animal. |
| Preservation artifact | change caused by preparation or storage | Curling, flattening, or tearing must be recorded before interpreting anatomy. |
| Individual variation | differences among specimens | One model specimen is not a universal body. |
The split between Proficient and Mastery is structure and function together: not just pointing to the gizzard, but saying what it does and why its wall is muscular. Ask “so what does that structure do?”
| Criterion | Developing | Proficient | Mastery |
|---|---|---|---|
| Instrument handling & safe technique | Grips the scalpel, scissors, forceps, or probe awkwardly; cuts too hard or too deep; 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, working safely for both the student and the specimen; this technique criterion requires educator-observed approved practical work. |
| Careful exposure & observation | Cuts before looking and tears or destroys structures while opening the specimen. | Opens the specimen roughly along the correct line but disturbs organs before observing them. | Opens the specimen cleanly along the dorsal midline without damaging structures, and observes the layout before disturbing anything; this exposure criterion requires educator-observed approved practical work. |
| Locating & naming external structures | Cannot point to the clitellum, segments, or setae, or tell anterior from posterior. | Finds a few external landmarks with prompting but confuses dorsal and ventral or miscounts segments. | Locates and names the clitellum, segments, and setae on the specimen, approved image, model, or virtual route and orients it correctly by anterior/posterior and dorsal/ventral. |
| Locating & naming internal structures | Guesses at the organs or names the wrong ones once the specimen is open. | Finds the larger organs but cannot reliably distinguish crop from gizzard or trace the blood vessel and nerve cord. | Locates and names the dorsal blood vessel, aortic arches, crop, gizzard, intestine, seminal vesicles, nephridia, and ventral nerve cord on the approved specimen, image, model, or virtual route. |
| Explaining structure & function (and specimen care) | Cannot say what a structure does, and lets the specimen dry out or handles it carelessly. | Explains one or two structures' functions but not the rest, and keeps the specimen moist only when reminded. | Explains why key structures do their jobs while stating segment-count variation, preservation artifacts, and route limits; specimen-care technique is credited only when observed. |
| Integration (cross-domain) | Makes no supported connection between the source and the science. | Uses the source but needs help connecting evidence, writing, or limitations to the science. | Independently connects History, Reading, and Writing using a cited source, appropriate evidence, a limitation, and a scientific explanation. |
Read these before you grade. They show what Mastery and Developing actually sound like, plus the edge cases where you should coach rather than decide on the spot.
Student: ______________________________________ Date: _______________ Guide: _________________________
| # | Criterion | Decision | Notes |
|---|---|---|---|
| 1 | Instrument handling & safe technique | Dev / Prof / Mast | |
| 2 | Careful exposure & observation | Dev / Prof / Mast | |
| 3 | Locating & naming external structures | Dev / Prof / Mast | |
| 4 | Locating & naming internal structures | Dev / Prof / Mast | |
| 5 | Explaining structure & function (and specimen care) | Dev / Prof / Mast | |
| 6 | Integration (cross-domain) | Dev / Prof / Mast |
☐ No ☐ Yes — for criterion: __________
Tokens left this term after this session (choose one): ☐ 3 ☐ 2 ☐ 1 ☐ None left
Each student has three tokens per term; each token retries one rubric criterion. Approved accommodations, equipment failures, and approved absences are handled separately and do not consume these tokens.
Dev = Developing · Prof = Proficient · Mast = Mastery · Unsure between two levels? Circle the lower one and note what a re-do would need.