Week 6 — Quiz (auto-graded) · The Integumentary System

Course: Anatomy & Physiology I (BIOL 2301 + BIOL 2101) · Silver Oak University (fictional sample) · Prof. Navarro
Objective tested: Objective 3 — the layers of the skin; the epidermal strata in order; melanin vs. keratin; accessory structures & glands; the skin's functions and thermoregulation (homeostasis).
Points: 10 (1 each) · Assignment group: Quizzes (10% of grade) · Due: end of Module 6.

This is the human-readable quiz with its vetted answer key and feedback. The import-ready Classic QTI is in F-quiz-week-06-qti.xml (generated by the shared validated script — parses with 10 items, every single-answer item exactly one correct). The reusable item-bank entries and the Canvas placement block are at the bottom of this file.

Blueprint

No trick questions; distractors target the Week 6 misconceptions named in the lecture outline. Item 2 is a "put the layers in order" item built as a matching item (order position → stratum), and Item 8 is the required true/false on the avascular epidermis.

Questions, key, and feedback

Q1 (MC). The epidermis (the outermost layer of the skin) is made of which tissue type?
- A. Keratinized stratified squamous epithelium ✅
- B. Dense irregular connective tissue
- C. Smooth muscle tissue
- D. Simple cuboidal epithelium with many blood vessels
Feedback: The epidermis is keratinized stratified squamous epithelium — packed, layered, flat (squamous) cells, toughened with keratin. (B describes the dermis; D is wrong twice — the epidermis is stratified, not simple cuboidal, and it has no blood vessels.)

Q2 (Matching — ordering). In thick skin the epidermis has five layers. Match each order position (from deepest to most superficial) to the correct stratum, so the layers read deep → superficial.
| Order position | Correct stratum |
|---|---|
| 1 — deepest layer | Stratum basale |
| 2 — second from deep | Stratum spinosum |
| 3 — middle layer | Stratum granulosum |
| 4 — fourth (thick skin only) | Stratum lucidum |
| 5 — most superficial layer | Stratum corneum |
Feedback: Deep → superficial: basale → spinosum → granulosum → lucidum → corneum. New cells are born in the basale and pushed up, dying as they go, until they're flat, dead, keratin-filled cells in the corneum. (The lucidum appears only in thick skin — palms and soles.)

Q3 (MC). What is the main function of melanin, the pigment made by melanocytes in the epidermis?
- A. It gives skin its toughness and water resistance the way keratin does
- B. It absorbs ultraviolet (UV) light, giving skin its color and protecting deeper cells from UV damage ✅
- C. It carries oxygen to the cells of the epidermis
- D. It produces the oily secretion that waterproofs the skin surface
Feedback: Melanin = pigment + UV shield. It absorbs UV light, protecting the DNA of deeper cells, and gives skin/hair their color. (A is keratin's job — toughness/waterproofing; C is false — the epidermis is avascular; D is sebum from sebaceous glands.)

Q4 (MC). Which statement best describes the dermis, the layer just deep to the epidermis?
- A. It is connective tissue containing blood vessels, nerves, glands, and hair follicles ✅
- B. It is avascular epithelium that contains no blood vessels at all
- C. It is a layer of adipose (fat) that is not part of the skin
- D. It is made of dead, keratin-filled cells that are constantly shed
Feedback: The dermis is connective tissue (collagen + elastin) and holds the blood vessels, nerves, glands, and hair follicles — it's the skin's living core. (B describes the epidermis; C describes the hypodermis; D describes the stratum corneum.)

Q5 (MC). When you become overheated, how does the skin help return body temperature toward its set point (thermoregulation, a homeostatic response)?
- A. Sweat glands release sweat that evaporates, and dermal blood vessels dilate to release heat ✅
- B. Sweat glands shut off and dermal blood vessels constrict to trap heat
- C. The epidermis produces extra keratin to insulate the body
- D. Melanocytes release melanin to cool the blood
Feedback: To cool down, eccrine sweat glands release sweat (which carries heat away as it evaporates) and dermal vessels dilate (vasodilation) to radiate heat. This opposes the temperature rise — negative feedback. (B is the cold response; C and D are not thermoregulatory mechanisms.)

Q6 (Multiple answer — select all that apply). Which of the following are true functions of the integumentary system (the skin and its accessory structures)?
- A. Protection — acting as a physical barrier against pathogens, UV light, and injury ✅
- B. Thermoregulation — helping keep body temperature in range through sweating and blood-vessel changes ✅
- C. Vitamin D synthesis when UV light strikes the skin ✅
- D. Sensation — detecting touch, pressure, temperature, and pain ✅
- E. Digestion of food into absorbable nutrients
- F. Production of ATP as the body's main energy source
Feedback: The skin's functions are protection, thermoregulation, sensation, vitamin D synthesis, and excretion (A–D true). Digestion (E) belongs to the digestive system; ATP production (F) happens in mitochondria during cellular respiration — both are the week's distractors.

Q7 (Matching). Match each skin gland to what it produces or does.
| Gland | Correct secretion / role |
|---|---|
| Sebaceous gland | Sebum (an oily secretion that lubricates and waterproofs skin and hair) |
| Eccrine sweat gland | Watery sweat used for thermoregulation by evaporative cooling |
| Apocrine sweat gland | A thick secretion in the armpit and groin that bacteria break down to cause body odor |
| Ceruminous gland | Cerumen (earwax) in the ear canal |
Feedback: Sebaceous → sebum (oil); eccrine sweat → watery cooling sweat; apocrine → odor-related secretion; ceruminous → earwax. The common mix-up is swapping the oil gland (sebaceous) with the sweat glands (sudoriferous).

Q8 (True / False). "The epidermis is rich in blood vessels, which deliver oxygen and nutrients directly to its cells."
- True
- False ✅
Feedback: False. The epidermis is avascular — it has no blood vessels. Its cells are fed by diffusion from the vessels in the dermis below, which is why the surface cells (farthest from that supply) eventually die. This is the week's #1 misconception.

Q9 (MC). Which epidermal layer is the deepest, containing the stem cells that constantly divide to produce new keratinocytes?
- A. Stratum corneum
- B. Stratum granulosum
- C. Stratum basale ✅
- D. Stratum lucidum
Feedback: The stratum basale is the deepest epidermal layer and the stem-cell factory — new keratinocytes are born here and pushed upward. (The corneum is the dead surface; the lucidum is a thick-skin-only layer near the top.)

Q10 (MC). The stratum corneum is made of many layers of flattened, dead, keratin-filled cells. How does this structure serve its function?
- A. The tough, keratin-filled dead cells form a barrier that resists abrasion and water loss and blocks microbes ✅
- B. The living, blood-rich cells rapidly heal cuts by dividing
- C. The clear cells let UV light pass through to make vitamin D
- D. The fat stored in these cells insulates the body against heat loss
Feedback: Structure determines function: flat, dead, keratin-packed cells make the corneum a tough barrier against abrasion, water loss, and microbes. (B is false — these cells are dead and avascular; C and D describe other structures, not the corneum.)

Answer key (quick reference)

Quality gate (self-checked): each single-answer item has exactly one correct option; the multiple-answer item (Q6) lists all four true functions (A, B, C, D) and requires the digestion (E) and ATP (F) distractors to be left unselected; the two matching items pair each stem to a distinct response; the ordering item (Q2) places the five epidermal strata correctly deep→superficial (basale → spinosum → granulosum → lucidum → corneum); the true/false (Q8) keys the avascular-epidermis misconception to False. Every anatomical fact — the epidermis as keratinized stratified squamous and avascular, the strata order, melanin vs. keratin, the dermis as connective tissue, the gland secretions, and thermoregulation as negative feedback — is verified against standard anatomy (cross-checked against OpenStax A&P 2e §5.1–5.2 and the InnerBody integumentary reference). Anatomy-accuracy gate: PASS. The quantitative gate does not apply this week — there is no computation in this quiz (Week 6 is conceptual; the quantitative pockets are the Week 2 pH and Week 3 osmolarity labs, with the Week 12 membrane-potential overview).

Item-bank entries (for variants + the midterm/final)

All ten items are tagged course=BIOL2301 · week=6 · objective=3 · topic=integumentary-system and deposited in Item Bank: Week 6 — The Integumentary System. The midterm (Week 8) and the per-term variant updates draw fresh items from this bank. (Tags: q1 epidermis-tissue-type, q2 epidermal-strata-order, q3 melanin-vs-keratin, q4 dermis-connective, q5 thermoregulation, q6 skin-functions, q7 gland-secretion-match, q8 epidermis-avascular, q9 stratum-basale, q10 corneum-structure-function.)

Canvas placement block

canvas_object   = Quizzes::Quiz
title           = "Week 6 Quiz — The Integumentary System"
assignment_group = "Quizzes"
points_possible = 10
grading_type    = points
due_offset_days = 6        # 6 days after module start
published       = true
shuffle_answers = true
provenance      = "~ Prof. Navarro's edition · Fall 2026 · built with thecoursemaker.com"