Biol 251 module 4 Exam question and
assured answers 2026/2027
1. What are the three main layers of the skin from superficial to deep?
A. Epidermis, dermis, hypodermis
B. Hypodermis, dermis, epidermis
C. Dermis, epidermis, hypodermis
D. Epidermis, hypodermis, dermis
Correct Answer: A
Rationale: The three main layers of the skin are the epidermis (superficial), dermis
(middle), and hypodermis (deep, also called subcutaneous layer).
2. The epidermis is composed of which type of tissue?
A. Stratified squamous epithelium
B. Simple squamous epithelium
C. Stratified cuboidal epithelium
D. Simple columnar epithelium
Correct Answer: A
Rationale: The epidermis is composed of stratified squamous epithelium, which
provides protection against abrasion and water loss.
3. The most superficial layer of the epidermis is the:
A. Stratum basale
B. Stratum spinosum
C. Stratum granulosum
D. Stratum corneum
Correct Answer: D
Rationale: The stratum corneum is the most superficial layer of the epidermis,
consisting of dead, keratinized cells.
4. The deepest layer of the epidermis, responsible for cell division, is the:
,A. Stratum corneum
B. Stratum lucidum
C. Stratum basale
D. Stratum granulosum
Correct Answer: C
Rationale: The stratum basale (germinativum) is the deepest layer of the epidermis and
is responsible for cell division.
5. Which layer of the epidermis is only found in thick skin (palms and soles)?
A. Stratum corneum
B. Stratum lucidum
C. Stratum granulosum
D. Stratum spinosum
Correct Answer: B
Rationale: The stratum lucidum is found only in thick skin, such as the palms and soles
of the feet.
6. Which cells in the epidermis produce keratin?
A. Melanocytes
B. Keratinocytes
C. Langerhans cells
D. Merkel cells
Correct Answer: B
Rationale: Keratinocytes are the most abundant cells in the epidermis and produce
keratin, a fibrous protein that provides protection.
7. Which cells in the epidermis produce melanin?
A. Keratinocytes
B. Melanocytes
C. Langerhans cells
D. Merkel cells
Correct Answer: B
Rationale: Melanocytes produce melanin, the pigment that gives skin its color and
protects against UV radiation.
,8. The dermis is composed of which type of tissue?
A. Epithelial tissue
B. Connective tissue
C. Muscle tissue
D. Nervous tissue
Correct Answer: B
Rationale: The dermis is composed of dense irregular connective tissue, containing
collagen and elastic fibers.
9. The dermis is divided into which two layers?
A. Stratum corneum and stratum basale
B. Papillary layer and reticular layer
C. Epidermis and hypodermis
D. Stratum granulosum and stratum spinosum
Correct Answer: B
Rationale: The dermis is divided into the papillary layer (superficial) and reticular layer
(deep).
10. The papillary layer of the dermis contains:
A. Dermal papillae
B. Blood vessels
C. Nerve endings
D. All of the above
Correct Answer: D
Rationale: The papillary layer contains dermal papillae, blood vessels, and nerve
endings.
11. The reticular layer of the dermis contains:
A. Collagen fibers
B. Elastic fibers
C. Blood vessels
D. All of the above
, Correct Answer: D
Rationale: The reticular layer contains collagen fibers, elastic fibers, and blood vessels.
12. The hypodermis is also known as the:
A. Subcutaneous layer
B. Epidermis
C. Dermis
D. Stratum corneum
Correct Answer: A
Rationale: The hypodermis is also called the subcutaneous layer or superficial fascia.
13. Which of the following is NOT found in the epidermis?
A. Melanocytes
B. Keratinocytes
C. Blood vessels
D. Langerhans cells
Correct Answer: C
Rationale: The epidermis is avascular (no blood vessels). Blood vessels are found in the
dermis and hypodermis.
14. What is the function of Langerhans cells in the epidermis?
A. Produce melanin
B. Produce keratin
C. Immune response
D. Sense touch
Correct Answer: C
Rationale: Langerhans cells are immune cells in the epidermis that help initiate an
immune response.
15. What is the function of Merkel cells in the epidermis?
A. Produce melanin
B. Produce keratin
C. Immune response
D. Sense touch
assured answers 2026/2027
1. What are the three main layers of the skin from superficial to deep?
A. Epidermis, dermis, hypodermis
B. Hypodermis, dermis, epidermis
C. Dermis, epidermis, hypodermis
D. Epidermis, hypodermis, dermis
Correct Answer: A
Rationale: The three main layers of the skin are the epidermis (superficial), dermis
(middle), and hypodermis (deep, also called subcutaneous layer).
2. The epidermis is composed of which type of tissue?
A. Stratified squamous epithelium
B. Simple squamous epithelium
C. Stratified cuboidal epithelium
D. Simple columnar epithelium
Correct Answer: A
Rationale: The epidermis is composed of stratified squamous epithelium, which
provides protection against abrasion and water loss.
3. The most superficial layer of the epidermis is the:
A. Stratum basale
B. Stratum spinosum
C. Stratum granulosum
D. Stratum corneum
Correct Answer: D
Rationale: The stratum corneum is the most superficial layer of the epidermis,
consisting of dead, keratinized cells.
4. The deepest layer of the epidermis, responsible for cell division, is the:
,A. Stratum corneum
B. Stratum lucidum
C. Stratum basale
D. Stratum granulosum
Correct Answer: C
Rationale: The stratum basale (germinativum) is the deepest layer of the epidermis and
is responsible for cell division.
5. Which layer of the epidermis is only found in thick skin (palms and soles)?
A. Stratum corneum
B. Stratum lucidum
C. Stratum granulosum
D. Stratum spinosum
Correct Answer: B
Rationale: The stratum lucidum is found only in thick skin, such as the palms and soles
of the feet.
6. Which cells in the epidermis produce keratin?
A. Melanocytes
B. Keratinocytes
C. Langerhans cells
D. Merkel cells
Correct Answer: B
Rationale: Keratinocytes are the most abundant cells in the epidermis and produce
keratin, a fibrous protein that provides protection.
7. Which cells in the epidermis produce melanin?
A. Keratinocytes
B. Melanocytes
C. Langerhans cells
D. Merkel cells
Correct Answer: B
Rationale: Melanocytes produce melanin, the pigment that gives skin its color and
protects against UV radiation.
,8. The dermis is composed of which type of tissue?
A. Epithelial tissue
B. Connective tissue
C. Muscle tissue
D. Nervous tissue
Correct Answer: B
Rationale: The dermis is composed of dense irregular connective tissue, containing
collagen and elastic fibers.
9. The dermis is divided into which two layers?
A. Stratum corneum and stratum basale
B. Papillary layer and reticular layer
C. Epidermis and hypodermis
D. Stratum granulosum and stratum spinosum
Correct Answer: B
Rationale: The dermis is divided into the papillary layer (superficial) and reticular layer
(deep).
10. The papillary layer of the dermis contains:
A. Dermal papillae
B. Blood vessels
C. Nerve endings
D. All of the above
Correct Answer: D
Rationale: The papillary layer contains dermal papillae, blood vessels, and nerve
endings.
11. The reticular layer of the dermis contains:
A. Collagen fibers
B. Elastic fibers
C. Blood vessels
D. All of the above
, Correct Answer: D
Rationale: The reticular layer contains collagen fibers, elastic fibers, and blood vessels.
12. The hypodermis is also known as the:
A. Subcutaneous layer
B. Epidermis
C. Dermis
D. Stratum corneum
Correct Answer: A
Rationale: The hypodermis is also called the subcutaneous layer or superficial fascia.
13. Which of the following is NOT found in the epidermis?
A. Melanocytes
B. Keratinocytes
C. Blood vessels
D. Langerhans cells
Correct Answer: C
Rationale: The epidermis is avascular (no blood vessels). Blood vessels are found in the
dermis and hypodermis.
14. What is the function of Langerhans cells in the epidermis?
A. Produce melanin
B. Produce keratin
C. Immune response
D. Sense touch
Correct Answer: C
Rationale: Langerhans cells are immune cells in the epidermis that help initiate an
immune response.
15. What is the function of Merkel cells in the epidermis?
A. Produce melanin
B. Produce keratin
C. Immune response
D. Sense touch
