,BIO 201 Exam 2 – Anatomy & Physiology I
(2026) Q&A | StraighterLine
1. The outermost layer of the epidermis, composed of dead, keratinized cells, is
the:
A) Stratum corneum
B) Stratum lucidum
C) Stratum granulosum
D) Stratum spinosum
Correct Answer: Stratum corneum
Rationale: The stratum corneum is the most superficial epidermal layer,
consisting of up to 30 layers of dead, scaly keratinocytes that provide a tough,
waterproof barrier. The other layers lie deeper and contain living or dying cells.
2. The layer of the epidermis found only in thick skin is the:
A) Stratum corneum
B) Stratum lucidum
C) Stratum basale
D) Stratum spinosum
Correct Answer: Stratum lucidum
,Rationale: The stratum lucidum is a clear, thin layer of dead keratinocytes
present only in thick skin, such as on the palms and soles. It lies between the
stratum granulosum and stratum corneum.
3. The deepest layer of the epidermis, where active cell division occurs, is the:
A) Stratum corneum
B) Stratum granulosum
C) Stratum basale
D) Stratum lucidum
Correct Answer: Stratum basale
Rationale: The stratum basale is a single row of cuboidal or columnar cells
attached to the basement membrane. These stem cells divide continuously to
replace the more superficial keratinocytes.
4. The pigment primarily responsible for skin color and UV protection is:
A) Carotene
B) Hemoglobin
C) Keratin
D) Melanin
Correct Answer: Melanin
, Rationale: Melanin, produced by melanocytes, absorbs ultraviolet radiation and
gives skin its brown to black hues. Carotene contributes a yellowish tint,
hemoglobin adds reddish tones, and keratin is structural.
5. The dermis layer composed of areolar tissue that allows motility of white
blood cells is the:
A) Papillary layer
B) Reticular layer
C) Hypodermis
D) Stratum basale
Correct Answer: Papillary layer
Rationale: The papillary layer is the superficial region of the dermis, made of
loose areolar connective tissue. It contains capillaries and allows immune cell
movement. The reticular layer is dense irregular tissue.
6. The thick collagen layer of the dermis responsible for stretch marks is the:
A) Papillary layer
B) Reticular layer
C) Stratum corneum
D) Basement membrane
Correct Answer: Reticular layer
(2026) Q&A | StraighterLine
1. The outermost layer of the epidermis, composed of dead, keratinized cells, is
the:
A) Stratum corneum
B) Stratum lucidum
C) Stratum granulosum
D) Stratum spinosum
Correct Answer: Stratum corneum
Rationale: The stratum corneum is the most superficial epidermal layer,
consisting of up to 30 layers of dead, scaly keratinocytes that provide a tough,
waterproof barrier. The other layers lie deeper and contain living or dying cells.
2. The layer of the epidermis found only in thick skin is the:
A) Stratum corneum
B) Stratum lucidum
C) Stratum basale
D) Stratum spinosum
Correct Answer: Stratum lucidum
,Rationale: The stratum lucidum is a clear, thin layer of dead keratinocytes
present only in thick skin, such as on the palms and soles. It lies between the
stratum granulosum and stratum corneum.
3. The deepest layer of the epidermis, where active cell division occurs, is the:
A) Stratum corneum
B) Stratum granulosum
C) Stratum basale
D) Stratum lucidum
Correct Answer: Stratum basale
Rationale: The stratum basale is a single row of cuboidal or columnar cells
attached to the basement membrane. These stem cells divide continuously to
replace the more superficial keratinocytes.
4. The pigment primarily responsible for skin color and UV protection is:
A) Carotene
B) Hemoglobin
C) Keratin
D) Melanin
Correct Answer: Melanin
, Rationale: Melanin, produced by melanocytes, absorbs ultraviolet radiation and
gives skin its brown to black hues. Carotene contributes a yellowish tint,
hemoglobin adds reddish tones, and keratin is structural.
5. The dermis layer composed of areolar tissue that allows motility of white
blood cells is the:
A) Papillary layer
B) Reticular layer
C) Hypodermis
D) Stratum basale
Correct Answer: Papillary layer
Rationale: The papillary layer is the superficial region of the dermis, made of
loose areolar connective tissue. It contains capillaries and allows immune cell
movement. The reticular layer is dense irregular tissue.
6. The thick collagen layer of the dermis responsible for stretch marks is the:
A) Papillary layer
B) Reticular layer
C) Stratum corneum
D) Basement membrane
Correct Answer: Reticular layer
