Anatomy & Physiology I with Lab | Portage Learning | Q & A |
2026/2027 Edition (PDF)
1. Which of the following best describes the primary function of the integumentary system?
A) To provide a rigid framework for the body
B) To protect the body from environmental hazards
C) To generate movement through muscle contraction
D) To filter waste products from the blood
Correct Answer: To protect the body from environmental hazards
Rationale: The integumentary system's primary role is to act as a protective barrier against physical,
chemical, and biological threats. The skeletal system provides the rigid framework, the muscular system
generates movement, and the urinary system filters blood.
2. What are the three main layers of the skin, from superficial to deep?
A) Epidermis, hypodermis, dermis
B) Epidermis, dermis, hypodermis
C) Dermis, epidermis, hypodermis
D) Hypodermis, dermis, epidermis
Correct Answer: Epidermis, dermis, hypodermis
Rationale: The skin is composed of three primary layers. The outermost layer is the epidermis, followed
by the dermis, and the deepest layer is the hypodermis (subcutaneous layer).
3. Which of the following is the most superficial layer of the epidermis?
A) Stratum basale
B) Stratum spinosum
,C) Stratum granulosum
D) Stratum corneum
Correct Answer: Stratum corneum
Rationale: The stratum corneum is the outermost layer of the epidermis, consisting of many layers of
dead, keratinized cells. The stratum basale is the deepest layer, followed by the stratum spinosum and
stratum granulosum.
4. Which layer of the epidermis is responsible for continuous cell division and replacement?
A) Stratum corneum
B) Stratum granulosum
C) Stratum basale
D) Stratum spinosum
Correct Answer: Stratum basale
Rationale: The stratum basale (or stratum germinativum) is the deepest epidermal layer where new cells
are produced through mitosis. These cells are then pushed upward toward the surface to replace shed
cells.
5. The layers of the epidermis, from deep to superficial, are:
A) Stratum corneum, stratum granulosum, stratum spinosum, stratum basale
B) Stratum basale, stratum spinosum, stratum granulosum, stratum corneum
C) Stratum basale, stratum granulosum, stratum spinosum, stratum corneum
D) Stratum corneum, stratum spinosum, stratum granulosum, stratum basale
Correct Answer: Stratum basale, stratum spinosum, stratum granulosum, stratum corneum
, Rationale: The correct order from deepest to most superficial is: stratum basale, stratum spinosum,
stratum granulosum, and stratum corneum. This sequence represents the life cycle of a keratinocyte as
it matures and moves toward the surface.
6. Which cell type in the epidermis is primarily responsible for producing the protein keratin?
A) Melanocytes
B) Keratinocytes
C) Langerhans cells
D) Merkel cells
Correct Answer: Keratinocytes
Rationale: Keratinocytes are the most abundant cells in the epidermis and are responsible for producing
keratin, a tough, fibrous protein that gives the skin its protective properties. Melanocytes produce
melanin, Langerhans cells are immune cells, and Merkel cells are sensory receptors.
7. What is the primary function of melanocytes?
A) To produce keratin for waterproofing
B) To produce melanin for UV protection
C) To detect light touch
D) To initiate immune responses
Correct Answer: To produce melanin for UV protection
Rationale: Melanocytes are specialized cells located in the stratum basale that produce melanin, a
pigment that protects the skin from ultraviolet (UV) radiation. This helps prevent DNA damage in skin
cells.
8. Which layer of the skin contains blood vessels, nerve endings, and hair follicles?
A) Epidermis
B) Dermis