Ch. 5 Layers of the Skin Cards

These flashcards cover key concepts from the lecture on the anatomy and physiology of the skin, including layers, cell types, functions, and associated disorders.

What are the main layers of the skin?

Epidermis, Dermis, and Hypodermis (Subcutaneous layer).

What is the primary cell type in the epidermis?

Keratinocytes.

What is the function of melanocytes in the skin?

They produce melanin, which gives skin its color and absorbs UV light.

What is the deepest layer of the epidermis?

Stratum basale.

What happens to keratinocytes as they migrate toward the skin's surface?

They die as they migrate.

What does the stratum granulosum layer begin to produce?

Keratohyalin, which forms keratin in superficial layers.

What type of tissue primarily makes up the dermis?

Dense connective tissue (CT).

What are dermal papillae and what is their function?

Small, nipple-like projections that increase surface area for blood supply and form fingerprints.

What are the two types of sweat glands found in the skin?

Eccrine (merocrine) and Apocrine sweat glands.

What is the most common type of skin cancer?

Basal cell carcinoma.

What is a first-degree burn?

A burn that affects only the epidermis, causing redness and minor pain.

What is the purpose of the arrector pili muscle?

To stand hair on end, causing goosebumps.

What are the two main regions of the dermis?

Papillary layer and Reticular layer.

What do eccrine sweat glands primarily help regulate?

Body temperature.

What is the ABCD rule used for?

To identify characteristics of melanoma skin cancer.

What is one function of the integumentary system?

Protection against environmental hazards.

What is the ABCD rule in skin cancer detection?

a guideline for the evaluation of moles and skin lesions to assess the risk of melanoma. It stands for Asymmetry, Border irregularity, Color variation, and Diameter greater than 6 mm.

What is the epidermis?

is the outermost layer of skin, composed mainly of keratinized stratified squamous epithelium. It provides a protective barrier against environmental damage.

What is the dermis?

is the middle layer of skin, located beneath the epidermis. It contains connective tissue, blood vessels, hair follicles, and glands, providing strength and elasticity to the skin.

What is subcutaneous tissue?

also known as hypodermis, is the deepest layer of skin. It consists of loose connective tissue and fat, which helps insulate the body and absorb shock.

What are keratinocytes?

are the predominant cell type in the epidermis, responsible for producing keratin, a protein that helps waterproof the skin and protects against environmental damage.

What are melanocytes?

are cells found in the epidermis that produce melanin, the pigment responsible for the color of skin and hair. They play a crucial role in protecting the skin from UV radiation.

What are Langerhans cells?

are specialized immune cells located in the epidermis. They help detect pathogens and initiate immune responses to protect the skin from infections.

What are Merkel cells?

are specialized cells in the epidermis that function as mechanoreceptors, playing a role in the sensation of touch. They are associated with sensory nerve endings.

What is thick skin?

is a type of skin that has a greater epidermal thickness, typically found on the palms of the hands and soles of the feet. It contains five layers of the epidermis, including a prominent stratum corneum, and lacks hair follicles and sebaceous glands.

What is thin skin?

is a type of skin that has a thinner epidermal layer, found on most of the body, including the face. It consists of four layers of the epidermis and contains hair follicles, sebaceous glands, and sweat glands.

What is the stratum corneum?

is the outermost layer of the epidermis, composed of dead keratinized cells. It serves as a protective barrier against environmental damage and water loss.

What is the stratum lucidum?

is a thin, translucent layer found only in thick skin, such as on the palms and soles. It provides an additional layer of protection and helps reduce friction.

What is the stratum granulosum?

is the layer of the epidermis where keratinocytes begin to flatten and lose their nuclei. It contains keratohyalin granules that help form keratin in the upper layers.

What is the stratum spinosum?

is the layer of the epidermis where keratinocytes are connected by desmosomes, providing strength and flexibility. It also contains Langerhans cells for immune defense.

What is the stratum basale?

is the deepest layer of the epidermis, consisting of a single row of actively dividing keratinocytes. It is responsible for the continuous regeneration of the epidermis and contains melanocytes and Merkel cells.

What are hair follicles?

are small, tubular structures in the skin from which hair grows. They are composed of keratinized cells and are involved in the production of hair and its associated features.

What are sebaceous glands?

are small glands in the skin that secrete an oily substance called sebum, which helps to lubricate and protect the skin and hair from drying out.

What are sweat glands?

are exocrine glands in the skin that produce sweat. There are two types: eccrine glands, which are involved in thermoregulation, and apocrine glands, which are associated with body odor.

What are nails?

are hard, keratinized structures that grow from the nail matrix and protect the tips of fingers and toes. They also enhance the ability to grasp and manipulate small objects.

What are sebaceous glands?

are small glands in the skin that secrete an oily substance called sebum. Sebum helps to moisturize and protect the skin and hair, preventing dryness.

What are eccrine sweat glands?

are a type of sweat gland distributed widely throughout the body. They produce a watery sweat that aids in thermoregulation and helps cool the body through evaporation.

What are apocrine sweat glands?

are found primarily in areas such as the armpits and genital regions. They secrete a thicker, milky sweat that is associated with body odor when broken down by bacteria on the skin.

What are mammary glands?

are specialized sweat glands that produce milk in females. They are considered accessory structures of the skin and are important for feeding infants.

What are ceruminous glands?

are modified sweat glands located in the ear canal. They secrete earwax (cerumen), which helps to protect the ear from dust, debris, and microorganisms.

Most Common Skin Disorder

bacterial, viral, and yeast infection

Less Common Skin DIsorder

skin cancer and burns

What is skin cancer?

is the abnormal growth of skin cells, often caused by exposure to ultraviolet (UV) radiation from the sun or tanning beds. It can develop in different forms, with varying severity and treatment methods.

What is squamous cell carcinoma (SCC)?

is a type of skin cancer that arises from squamous cells, which make up the outer layer of the skin. It often appears as a firm, red nodule or a flat, scaly lesion and is more aggressive than basal cell carcinoma.

What is melanoma?

is the most dangerous type of skin cancer that develops from melanocytes, the cells that produce pigment. It can spread quickly to other parts of the body if not detected early, appearing as a new or changing mole.

What is the ABCD rule in relation to melanoma?

is a guideline for identifying potential melanomas based on four criteria: A for Asymmetry, B for Border irregularity, C for Color variation, and D for Diameter larger than 6mm. This rule helps in the early detection of melanoma.

What are burns?

are injuries to the skin or deeper tissues caused by heat, chemicals, electricity, sunlight, or radiation. They can vary in severity and are categorized into first-degree, second-degree, and third-degree burns based on the depth of tissue damage.

What are first-degree burns?

affect only the outer layer of skin (epidermis), causing redness, minor swelling, and pain. They usually heal within a few days without scarring.

What are second-degree burns?

damage both the epidermis and the outer layer of the dermis, resulting in blisters, swelling, and severe pain. Healing can take weeks and may leave scarring.

What are third-degree burns?

involve all layers of the skin and may extend into underlying tissues. They can appear white, charred, or leathery and usually require medical intervention, skin grafts, and can result in significant scarring.