,WGU C156 Anatomy and Physiology Exam 2 | Q &
A | 2026 Edition | Western Governors University
1. Which layer of the epidermis is the deepest and is responsible for continuous cell division?**
A) Stratum corneum
B) Stratum granulosum
C) Stratum spinosum
D) Stratum basale
Correct Answer: D) Stratum basale
Rationale: The stratum basale (also called the stratum germinativum) is the deepest layer of the
epidermis, where cells undergo mitosis to produce new keratinocytes. These newly formed cells are
pushed upward toward the surface as they differentiate. The stratum corneum is the outermost layer of
dead cells, the stratum granulosum is where keratinization begins, and the stratum spinosum provides
strength and flexibility.
**2. Which epidermal cell type produces melanin, the pigment responsible for skin color?**
A) Keratinocyte
B) Langerhans cell
C) Melanocyte
D) Merkel cell
Correct Answer: C) Melanocyte
Rationale: Melanocytes are located in the stratum basale and produce melanin, a pigment that protects
the skin from ultraviolet (UV) radiation and contributes to skin color. Keratinocytes produce the
structural protein keratin, Langerhans cells are antigen-presenting immune cells, and Merkel cells
function as touch receptors.
**3. The papillary layer of the dermis is primarily composed of which type of connective tissue?**
,A) Dense irregular connective tissue
B) Areolar connective tissue
C) Adipose tissue
D) Reticular connective tissue
Correct Answer: B) Areolar connective tissue
Rationale: The papillary layer is the superficial layer of the dermis, composed of loose areolar connective
tissue. It contains dermal papillae that interlock with the epidermis, supplying nutrients to the avascular
epidermis and housing sensory receptors. The reticular layer is composed of dense irregular connective
tissue.
**4. Which of the following is NOT a function of the integumentary system?**
A) Protection against pathogens
B) Synthesis of vitamin D
C) Production of red blood cells
D) Thermoregulation
Correct Answer: C) Production of red blood cells
Rationale: The integumentary system provides protection, synthesizes vitamin D (with UV exposure),
and helps regulate body temperature through sweat and blood flow. Production of red blood cells
(hematopoiesis) occurs in the red bone marrow of the skeletal system, not the skin.
**5. Which type of sweat gland is most abundant in the skin and is primarily involved in
thermoregulation?**
A) Apocrine sweat gland
B) Eccrine sweat gland
C) Sebaceous gland
D) Ceruminous gland
, Correct Answer: B) Eccrine sweat gland
Rationale: Eccrine sweat glands are the most numerous and are found throughout the body. They
produce a watery sweat that helps cool the body through evaporation. Apocrine glands are found in
axillary and genital areas and become active at puberty; sebaceous glands secrete oil; and ceruminous
glands produce earwax.
**6. Which of the following bones is classified as a long bone?**
A) Scapula
B) Vertebra
C) Femur
D) Patella
Correct Answer: C) Femur
Rationale: Long bones are longer than they are wide and consist of a shaft (diaphysis) and two ends
(epiphyses). The femur is a classic example. The scapula is a flat bone, the vertebra is an irregular bone,
and the patella is a sesamoid bone.
**7. The structural unit of compact bone is the:**
A) Osteon
B) Trabecula
C) Lamella
D) Canaliculus
Correct Answer: A) Osteon
Rationale: The osteon (Haversian system) is the fundamental structural unit of compact bone. It consists
of concentric rings of bone matrix (lamellae) surrounding a central canal containing blood vessels and
nerves. Trabeculae are the structural units of spongy bone.
A | 2026 Edition | Western Governors University
1. Which layer of the epidermis is the deepest and is responsible for continuous cell division?**
A) Stratum corneum
B) Stratum granulosum
C) Stratum spinosum
D) Stratum basale
Correct Answer: D) Stratum basale
Rationale: The stratum basale (also called the stratum germinativum) is the deepest layer of the
epidermis, where cells undergo mitosis to produce new keratinocytes. These newly formed cells are
pushed upward toward the surface as they differentiate. The stratum corneum is the outermost layer of
dead cells, the stratum granulosum is where keratinization begins, and the stratum spinosum provides
strength and flexibility.
**2. Which epidermal cell type produces melanin, the pigment responsible for skin color?**
A) Keratinocyte
B) Langerhans cell
C) Melanocyte
D) Merkel cell
Correct Answer: C) Melanocyte
Rationale: Melanocytes are located in the stratum basale and produce melanin, a pigment that protects
the skin from ultraviolet (UV) radiation and contributes to skin color. Keratinocytes produce the
structural protein keratin, Langerhans cells are antigen-presenting immune cells, and Merkel cells
function as touch receptors.
**3. The papillary layer of the dermis is primarily composed of which type of connective tissue?**
,A) Dense irregular connective tissue
B) Areolar connective tissue
C) Adipose tissue
D) Reticular connective tissue
Correct Answer: B) Areolar connective tissue
Rationale: The papillary layer is the superficial layer of the dermis, composed of loose areolar connective
tissue. It contains dermal papillae that interlock with the epidermis, supplying nutrients to the avascular
epidermis and housing sensory receptors. The reticular layer is composed of dense irregular connective
tissue.
**4. Which of the following is NOT a function of the integumentary system?**
A) Protection against pathogens
B) Synthesis of vitamin D
C) Production of red blood cells
D) Thermoregulation
Correct Answer: C) Production of red blood cells
Rationale: The integumentary system provides protection, synthesizes vitamin D (with UV exposure),
and helps regulate body temperature through sweat and blood flow. Production of red blood cells
(hematopoiesis) occurs in the red bone marrow of the skeletal system, not the skin.
**5. Which type of sweat gland is most abundant in the skin and is primarily involved in
thermoregulation?**
A) Apocrine sweat gland
B) Eccrine sweat gland
C) Sebaceous gland
D) Ceruminous gland
, Correct Answer: B) Eccrine sweat gland
Rationale: Eccrine sweat glands are the most numerous and are found throughout the body. They
produce a watery sweat that helps cool the body through evaporation. Apocrine glands are found in
axillary and genital areas and become active at puberty; sebaceous glands secrete oil; and ceruminous
glands produce earwax.
**6. Which of the following bones is classified as a long bone?**
A) Scapula
B) Vertebra
C) Femur
D) Patella
Correct Answer: C) Femur
Rationale: Long bones are longer than they are wide and consist of a shaft (diaphysis) and two ends
(epiphyses). The femur is a classic example. The scapula is a flat bone, the vertebra is an irregular bone,
and the patella is a sesamoid bone.
**7. The structural unit of compact bone is the:**
A) Osteon
B) Trabecula
C) Lamella
D) Canaliculus
Correct Answer: A) Osteon
Rationale: The osteon (Haversian system) is the fundamental structural unit of compact bone. It consists
of concentric rings of bone matrix (lamellae) surrounding a central canal containing blood vessels and
nerves. Trabeculae are the structural units of spongy bone.
