,CHEM 103 Module 3 Exam | General
Chemistry I w/Lab | Portage Learning | Q & A
| 2026 Edition
1. Which of the following best defines the primary function of the integumentary system?
A) To provide a rigid framework for body movement
B) To protect the body from environmental damage and regulate temperature
C) To transport oxygen and nutrients to body tissues
D) To produce hormones that regulate metabolism
Correct Answer: To protect the body from environmental damage and regulate temperature
Rationale: The integumentary system's primary role is to serve as a physical barrier against pathogens,
UV radiation, and mechanical injury, while also maintaining body temperature through sweat and blood
vessel regulation. The skeletal system provides framework, the cardiovascular system transports
nutrients, and the endocrine system produces hormones.
2. What are the two main layers of the skin?
A) Epidermis and hypodermis
B) Dermis and subcutaneous tissue
C) Epidermis and dermis
D) Stratum corneum and stratum basale
Correct Answer: Epidermis and dermis
Rationale: The skin is composed of two primary layers: the outer epidermis and the underlying dermis.
The hypodermis (subcutaneous tissue) is a deeper layer of connective tissue that anchors the skin to
underlying structures.
3. The epidermis is composed primarily of which type of epithelium?
,A) Simple squamous epithelium
B) Stratified squamous epithelium
C) Simple columnar epithelium
D) Transitional epithelium
Correct Answer: Stratified squamous epithelium
Rationale: The epidermis is a stratified squamous epithelium that provides a protective, waterproof
barrier. Its multiple layers of cells are designed to withstand abrasion and prevent water loss.
4. Which of the following cell types in the epidermis is responsible for producing the pigment melanin?
A) Keratinocytes
B) Langerhans cells
C) Melanocytes
D) Merkel cells
Correct Answer: Melanocytes
Rationale: Melanocytes are dendritic cells located in the stratum basale that produce melanin, a
pigment that absorbs UV radiation and protects DNA from damage. Keratinocytes produce keratin,
Langerhans cells are immune cells, and Merkel cells are mechanoreceptors.
5. A researcher is studying cells that produce a fibrous protein to protect the skin from abrasion. Which
cell type is the focus of this study?
A) Melanocytes
B) Langerhans cells
C) Keratinocytes
D) Fibroblasts
Correct Answer: Keratinocytes
, Rationale: Keratinocytes are the most abundant cells in the epidermis and produce keratin, a tough,
fibrous protein that provides structural strength and protection. Fibroblasts produce collagen in the
dermis.
6. Which epidermal cells function as antigen-presenting cells to initiate immune responses?
A) Melanocytes
B) Langerhans cells
C) Keratinocytes
D) Merkel cells
Correct Answer: Langerhans cells
Rationale: Langerhans cells are specialized immune cells found in the stratum spinosum of the epidermis
that capture pathogens, process antigens, and initiate immune responses to protect the body from
invading microorganisms.
7. What is the deepest layer of the epidermis, where new cells are produced through mitosis?
A) Stratum corneum
B) Stratum granulosum
C) Stratum spinosum
D) Stratum basale
Correct Answer: Stratum basale
Rationale: The stratum basale (germinativum) is the deepest epidermal layer, attached to the basement
membrane. It contains stem cells that undergo continuous mitosis to produce new keratinocytes, which
then migrate superficially.
8. What is the most superficial layer of the epidermis, composed of dead, flattened keratinized cells?
A) Stratum basale
Chemistry I w/Lab | Portage Learning | Q & A
| 2026 Edition
1. Which of the following best defines the primary function of the integumentary system?
A) To provide a rigid framework for body movement
B) To protect the body from environmental damage and regulate temperature
C) To transport oxygen and nutrients to body tissues
D) To produce hormones that regulate metabolism
Correct Answer: To protect the body from environmental damage and regulate temperature
Rationale: The integumentary system's primary role is to serve as a physical barrier against pathogens,
UV radiation, and mechanical injury, while also maintaining body temperature through sweat and blood
vessel regulation. The skeletal system provides framework, the cardiovascular system transports
nutrients, and the endocrine system produces hormones.
2. What are the two main layers of the skin?
A) Epidermis and hypodermis
B) Dermis and subcutaneous tissue
C) Epidermis and dermis
D) Stratum corneum and stratum basale
Correct Answer: Epidermis and dermis
Rationale: The skin is composed of two primary layers: the outer epidermis and the underlying dermis.
The hypodermis (subcutaneous tissue) is a deeper layer of connective tissue that anchors the skin to
underlying structures.
3. The epidermis is composed primarily of which type of epithelium?
,A) Simple squamous epithelium
B) Stratified squamous epithelium
C) Simple columnar epithelium
D) Transitional epithelium
Correct Answer: Stratified squamous epithelium
Rationale: The epidermis is a stratified squamous epithelium that provides a protective, waterproof
barrier. Its multiple layers of cells are designed to withstand abrasion and prevent water loss.
4. Which of the following cell types in the epidermis is responsible for producing the pigment melanin?
A) Keratinocytes
B) Langerhans cells
C) Melanocytes
D) Merkel cells
Correct Answer: Melanocytes
Rationale: Melanocytes are dendritic cells located in the stratum basale that produce melanin, a
pigment that absorbs UV radiation and protects DNA from damage. Keratinocytes produce keratin,
Langerhans cells are immune cells, and Merkel cells are mechanoreceptors.
5. A researcher is studying cells that produce a fibrous protein to protect the skin from abrasion. Which
cell type is the focus of this study?
A) Melanocytes
B) Langerhans cells
C) Keratinocytes
D) Fibroblasts
Correct Answer: Keratinocytes
, Rationale: Keratinocytes are the most abundant cells in the epidermis and produce keratin, a tough,
fibrous protein that provides structural strength and protection. Fibroblasts produce collagen in the
dermis.
6. Which epidermal cells function as antigen-presenting cells to initiate immune responses?
A) Melanocytes
B) Langerhans cells
C) Keratinocytes
D) Merkel cells
Correct Answer: Langerhans cells
Rationale: Langerhans cells are specialized immune cells found in the stratum spinosum of the epidermis
that capture pathogens, process antigens, and initiate immune responses to protect the body from
invading microorganisms.
7. What is the deepest layer of the epidermis, where new cells are produced through mitosis?
A) Stratum corneum
B) Stratum granulosum
C) Stratum spinosum
D) Stratum basale
Correct Answer: Stratum basale
Rationale: The stratum basale (germinativum) is the deepest epidermal layer, attached to the basement
membrane. It contains stem cells that undergo continuous mitosis to produce new keratinocytes, which
then migrate superficially.
8. What is the most superficial layer of the epidermis, composed of dead, flattened keratinized cells?
A) Stratum basale
