Week 7 — A&P Lab / Scientific Inquiry · "Build a Bone"

Course: Anatomy & Physiology I (BIOL 2301 + BIOL 2101) · Silver Oak University (fictional sample) · Prof. Navarro
Objective: Objective 4 — identify the gross & microscopic structure of bone and classify bones by shape · SLO A (relate structure to function) · SLO B (use skeletal terminology correctly)
Worth 50 points · Labs group = 15% of the grade · Lab 7
Format: a guided exploration of a free virtual skeleton / anatomy atlas (no download, nothing to buy) — you'll identify long-bone parts and bone types, describe their structure→function, and then catch the AI's mistakes when it labels a bone.

This is the course's signature weekly component. Every instructional week has one A&P lab. This week's uses a free virtual skeleton; earlier weeks used a virtual atlas, a virtual microscope (histology), and PhET physiology simulations. All lab resources are links to external sites — nothing to buy or download.

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Part 1 — The Big Picture

This week you learned that bone is living tissue with a named architecture: the gross anatomy of a long bone (diaphysis, epiphysis, growth plate, periosteum, medullary cavity) and its microscopic build (compact bone made of osteons vs. spongy bone made of trabeculae), maintained by three cells — osteoblast, osteoclast, osteocyte. Today you'll find those structures on a real bone model and explain how each one's shape serves its job.

The scientific habit this builds: observation → precise identification → tying structure to function → checking your work against a reference. In A&P, naming a structure isn't the finish line — explaining what it does and why its form fits is.

Background (optional, ~5 min): the InnerBody Skeletal System page, "Microscopic Structure of Bones" and "Parts of Bones" sections — keep it open as your answer key for the gross and microscopic anatomy: 🔗 https://www.innerbody.com/image/skelfov.html

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Part 2 — Your Scientific Question & Hypothesis

Anatomy labs still start like any inquiry — with a question and a prediction you'll test against evidence (here, the bone model).

The question: Can you identify the parts of a long bone and the two bone tissue types on a virtual skeleton — and explain how each structure's form serves its function — accurately enough that another person could verify every label?

Before you start, write your hypothesis / prediction:

I predict that I can correctly identify the long-bone parts and bone types below and give a sound structure→function reason for each — and that when I ask an AI to label the same bone, it will make at least ______ error(s) I can catch (for example, swapping osteoblast/osteoclast or diaphysis/epiphysis).

(There's no "right" number — you're predicting how reliable the AI will be, then checking.)

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Part 3 — Materials & Procedure

You need (all free, in a browser):
- The InnerBody Skeletal System explorer (free, no download): 🔗 https://www.innerbody.com/image/skelfov.html
- Optional second reference: OpenStax A&P §6.3 "Bone Structure" 🔗 https://openstax.org/books/anatomy-and-physiology-2e/pages/6-3-bone-structure
- An approved chatbot (Gemini, Claude, or ChatGPT) for Part 6.

Procedure:
1. Open the Skeletal System explorer and find a long bone — the femur is ideal. Read the "Parts of Bones" and "Microscopic Structure of Bones" sections.
2. For each structure in the Part 4 table, find it (or read its description) and record (a) a one-line identification (what/where it is) and (b) one structure→function note (what it does).
3. Identify one bone of each shape class — a long, a short, a flat, and an irregular bone — by name.
4. Keep the InnerBody page (or OpenStax §6.3) open and check each of your own answers against it before moving on.

No specific atlas access? Any free virtual skeleton or 3D viewer works (e.g., GetBodySmart's Skeletal System: https://www.getbodysmart.com/skeletal-system/). The skill — identify the structure, tie it to its function, and verify it — is identical.

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Part 4 — Structure-Identification Table (fill this in)

Structure	What / where it is	One structure → function note
Diaphysis	______	______
Epiphysis	______	______
Epiphyseal (growth) plate	______	______
Periosteum	______	______
Medullary cavity	______	______
Compact bone (osteon)	______	______
Spongy bone (trabeculae)	______	______

Bone-shape classification (name one example bone of each):

Shape class	Example bone
Long	______
Short	______
Flat	______
Irregular	______

Use only standard terms: diaphysis, epiphysis, epiphyseal plate, periosteum, endosteum, medullary cavity, articular cartilage, compact (cortical) bone, osteon, spongy (cancellous) bone, trabeculae; shapes: long, short, flat, irregular.

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Part 5 — Identify the Reasoning

Answer in a sentence each:
1. Structure → function: Why is a long bone's shaft hollow (a medullary cavity) rather than solid? Give one advantage. (Think weight vs. strength — and what fills the space.)
2. The three bone cells are osteoblast, osteoclast, osteocyte. Which one would be most active in an astronaut who is losing bone in microgravity, and why? (Tie it to remodeling and mechanical stress.)
3. Pick compact OR spongy bone and explain how its microscopic structure (osteons vs. trabeculae) fits its job in the bone. (This is the structure→function habit.)

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Part 6 — AI-Critique Moment (required — this is the BYOAI step)

Now bring in your approved chatbot (Gemini, Claude, or ChatGPT) and be the anatomist who checks its labels.

1. Paste this to the chatbot: "Label the parts of a long bone (femur): the shaft, the ends, the growth plate, the outer membrane, and the marrow cavity. Then tell me which bone cell builds bone and which breaks it down to release calcium, and whether compact bone is made of osteons or trabeculae."
2. Check everything it says against the atlas and OpenStax §6.3:
   - Did it call the shaft the diaphysis and the ends the epiphyses (not reversed)? Chatbots flip these constantly.
   - Did it say osteoBlasts BUILD bone and osteoClasts BREAK IT DOWN (release calcium)? The reversed-cells error is the #1 slip in this unit.
   - Did it say compact bone is made of osteons and spongy bone of trabeculae (not the reverse)?
   - Did it keep the periosteum on the outer surface and the medullary cavity as the hollow shaft center?
3. Write 2–3 sentences reporting what the AI got right and at least one labeling error you caught and corrected (with the correct term). If it happened to get everything right, say how you verified each label against the atlas — that's the skill.

The habit all term: the tool drafts, you judge. A chatbot will confidently swap osteoblast and osteoclast or flip diaphysis and epiphysis — catching it is the point, and in the clinic it's not optional. Remember the hooks: blast Builds, clast Chews; diaphysis = shaft, epiphysis = end.

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Part 7 — What to Submit

Submit a single document (or text entry) with: your hypothesis/prediction, your completed Part 4 table (structures + shape classes), your Part 5 answers, and your Part 6 AI-critique paragraph. Due Sunday, Oct 18, 11:59 p.m. (50 points).

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Instructor answer key — REMOVE BEFORE PUBLISHING TO STUDENTS

Every structure and structure→function note below is verified against standard anatomy (OpenStax A&P §6.3; InnerBody Skeletal System).

Part 4 — verified identification table:

Structure	What / where it is	Structure → function
Diaphysis	The long, tube-shaped shaft of the bone	Acts as the bone's lever/column; its tubular shape resists bending with little material
Epiphysis	Each rounded end of the bone (at a joint)	Widened end spreads joint loads; capped by articular cartilage for smooth movement; holds spongy bone + red marrow
Epiphyseal (growth) plate	Band of cartilage between diaphysis and epiphysis (becomes the epiphyseal line in adults)	Where the bone lengthens during childhood growth
Periosteum	Tough membrane on the outer surface	Anchors tendons/muscles; carries blood vessels in; site of osteogenic cells for growth/repair
Medullary cavity	The hollow center of the shaft	Holds marrow (red → yellow with age); hollowing keeps the bone light without much loss of strength
Compact bone (osteon)	Dense outer bone built from osteons (rings of lamellae around a central canal)	Bears large loads; the ring-around-a-vessel design keeps dense bone nourished
Spongy bone (trabeculae)	Open lattice of trabeculae (struts) at the ends/interior, with red marrow in the gaps; no osteons	Reinforces along lines of stress — strength where needed, but light; houses red marrow (hematopoiesis)

Bone-shape classification (any correct example accepted): Long = femur / humerus / tibia / phalanx; Short = carpal / tarsal; Flat = sternum / rib / scapula / skull (cranial) bone / hip bone; Irregular = vertebra / sacrum / facial bone (e.g., sphenoid).

• Part 5: (1) A hollow shaft makes the bone much lighter while keeping nearly all of a solid bone's bending strength (a tube resists bending efficiently), and the cavity is useful space for marrow — strength + low weight + storage. (2) The osteoclast is most active — with no mechanical load in microgravity, remodeling shifts toward breakdown (osteoclasts resorb faster than osteoblasts build), so bone is lost (Wolff's law: bone adapts to the stress placed on it). (3) Example — compact bone's tightly packed osteons make a dense, strong outer shell that carries big loads, with each osteon's central canal keeping the living cells fed; OR spongy bone's trabeculae form a strut-work aligned to stress, giving strength with minimal weight and leaving gaps for red marrow.
• Part 6 (AI-critique): full credit for a specific catch — most commonly the AI swapping osteoblast and osteoclast (blast builds, clast breaks down), flipping diaphysis and epiphysis (diaphysis = shaft, epiphysis = end), or calling spongy bone "osteons" (osteons are compact bone; spongy = trabeculae). Full credit also if the student verified each label against the atlas and OpenStax.

Grading rubric — 50 points

Criterion	Full	Partial	None
Hypothesis / prediction — a clear prediction about both the structures and the AI's reliability (6)	6	3–4	0–2
Structure table (Part 4) — long-bone parts + compact/spongy + four shape classes identified correctly (18)	18	9–15	0–7
Reasoning (Part 5) — hollow-shaft advantage, the osteoclast/remodeling answer, and a sound compact-or-spongy structure→function point (14)	14	7–11	0–5
AI-critique (Part 6) — names a specific labeling error caught and corrected with the right term (8)	8	4–6	0–3
Anatomical language — uses standard skeletal terms correctly throughout (4)	4	2	0–1

Quality gate (self-checked): every structure and structure→function note in the key is verified against standard anatomy (OpenStax §6.3; InnerBody Skeletal System) — diaphysis = shaft, epiphysis = end, epiphyseal plate = growth cartilage, periosteum = outer membrane, medullary cavity = hollow marrow center; compact = osteons, spongy = trabeculae; osteoBlast builds, osteoClast resorbs/releases Ca²⁺, osteocyte maintains; red marrow = hematopoiesis. No structure is mislabeled. Anatomy-accuracy gate: PASS. (No arithmetic in this lab — calcium regulation is treated qualitatively this week — so the quantitative gate does not apply this week.)

Provenance: free virtual skeleton (InnerBody Skeletal System) + OpenStax A&P §6.3, links only, each verified live 2026-06-27; no license/CC claims.