Anatomy Chapter 5 Flashcards

Questions and Answers

What tissue types compose the epidermis and dermis?

The epidermis is composed of stratified squamous epithelium, and the dermis is composed of dense irregular connective tissue proper.

List the major layers of the epidermis.

Stratum Basale, Stratum Spinosum, Stratum Granulosum, Stratum Lucidum, Stratum Corneum.

What is the function of the stratum corneum?

The stratum corneum protects the skin against abrasion and penetration and waterproofs the skin.

What are the two layers of the dermis?

Papillary and Reticular layers. Signup and view all the answers

What factors contribute to skin color?

Melanin, carotene, and hemoglobin. Signup and view all the answers

What is the main function of sweat glands?

To regulate body temperature and eliminate waste products. Signup and view all the answers

What separates eccrine from apocrine sweat glands?

Eccrine glands are abundant on the palms and soles and secrete a hypotonic filtrate, while apocrine glands are located in the axillary and anogenital areas and secrete a thicker fluid. Signup and view all the answers

What are the three layers of keratinized cells in hair?

Medulla, Cortex, Cuticle. Signup and view all the answers

What type of cancer is the least malignant?

Basal Cell Carcinoma Signup and view all the answers

Why are serious burns life threatening?

They can cause dehydration and infection due to loss of body fluids containing proteins and electrolytes. Signup and view all the answers

What is the 'Rule of Nines' used for?

To determine the extent of burns on the body. Signup and view all the answers

What defines a 2nd degree burn?

It damages the epidermis and upper region of the dermis, causing blisters. Signup and view all the answers

What characterizes a 3rd degree burn?

Grey-white or blackened appearance with nerve endings destroyed, resulting in no pain. Signup and view all the answers

Study Notes

Tissue Types in Skin

Epidermis: Composed of stratified squamous epithelium; 4-5 layers; thicker in palms, fingertips, and soles.
Dermis: Composed of dense irregular connective tissue; consists of two layers.

Layers of the Epidermis

Stratum Basale: Deepest layer; single row of stem cells; rapid division; 10%-25% melanocytes.
Stratum Spinosum: Several layers thick; irregular keratinocytes with desmosomes; spiny appearance due to tissue preparation.
Stratum Granulosum: 3-5 layers thick; keratinization occurs; cells filled with keratin; lamellar granules provide water resistance.
Stratum Lucidum: Only in thick skin; 1-2 rows of clear, dead keratinocytes.
Stratum Corneum: Outermost layer; 20-30 cell layers thick; provides protection and waterproofing; made up of dead keratin-filled cells.

Dermis Layers

Papillary Layer: Loose areolar connective tissue; 20% of dermis; contains blood vessels and dermal papillae.
Reticular Layer: Deeper layer; dense irregular tissue; accounts for 80% of dermal thickness.

Skin Color Factors

Determined by melanin, carotene, and hemoglobin.
Sun exposure can darken and damage skin, increasing risk of skin cancer.

Pigments Affecting Skin Color

Melanin: Polymer of tyrosine; provides natural protection against UV.
Carotene: Yellow-orange pigment; found in thick skin areas; can convert to vitamin A.
Hemoglobin: Contributes to pinkish hue; visible through the transparent epidermis, more pronounced in Caucasian skin.

Sweat Glands

Eccrine: Abundant on palms and forehead; coiled tubular glands; produce sweat for thermoregulation.
Apocrine: Found in axillary and anogenital areas; secrete milky sweat with fatty substances; function begins at puberty; odor can develop with bacterial interaction.

Oil Glands (Sebaceous)

Simple branched alveolar glands; secrete sebum; found everywhere except palms and soles; linked to hair follicles.

Hair Follicle Components

Hair Bulb: Deep end of follicle where hair growth begins.
Hair Follicle Receptor: Sensory nerve endings wrapped around each hair bulb.
Hair Papilla: Contains capillaries supplying nutrients for hair growth.
Wall of Hair Follicle: Composed of connective and epithelial sheaths.
Hair Matrix: Site of active cell division leading to hair production.

Hair Structure

Shaft: Visible part of hair; keratinization complete.
Root: Portion embedded in the follicle; keratinization ongoing.

Hair Composition

Medulla: Central core with soft keratin.
Cortex: Bulky layer surrounding the medulla.
Cuticle: Overlapping outer layer; provides strength.

Skin Functions

Protection: Three barriers—chemical, physical, biological.
Body Temperature Regulation: Insensible perspiration; sweat glands help cool the body.
Cutaneous Sensation: Rich supply of sensory receptors; respond to external stimuli.
Metabolic Functions: Vitamin D synthesis; chemical conversions.
Blood Reservoir: Can hold 5% of total body blood volume; redistributes blood as needed.
Excretion: Removes waste products through sweat.

Skin Cancer Types

Basal Cell Carcinoma: Most common and least malignant; shiny nodules; nearly 99% cure rate.
Squamous Cell Carcinoma: Arises from keratinocytes; lesions appear as scaly red patches; good cure prospects if caught early.
Melanoma: Most dangerous; highly metastatic; arises from melanocytes; early detection crucial.

Burns

Life Threatening: Serious burns cause dehydration and infection; can lead to renal failure and shock.
Extent Assessment: Rule of nines divides body into 11 areas, each accounting for 9% of total body area.
Burn Degrees:
- 1st Degree: Affects only epidermis; redness and pain; heals in 2-3 days.
- 2nd Degree: Involves epidermis and part of dermis; blisters; heals in weeks with minimal scarring.
- 3rd Degree: Destroys entire skin depth; may require skin grafts; little to no pain due to nerve damage.

Description

Test your knowledge of the tissue types and layers of the epidermis and dermis. This quiz covers the major layers and their functions, enhancing your understanding of skin anatomy. Perfect for students preparing for exams or looking to reinforce their learning.