Podcast
Questions and Answers
Which layer of the epidermis is primarily responsible for waterproofing the skin?
Which layer of the epidermis is primarily responsible for waterproofing the skin?
The hypodermis is composed primarily of epithelial tissue.
The hypodermis is composed primarily of epithelial tissue.
False (B)
What is the name of the non-pigmented hair that covers the fetus?
What is the name of the non-pigmented hair that covers the fetus?
Lanugo
The production of melanin is stimulated by ______ light.
The production of melanin is stimulated by ______ light.
Signup and view all the answers
Match the following skin structures with their corresponding functions:
Match the following skin structures with their corresponding functions:
Signup and view all the answers
Which layer of the skin is the outermost and avascular?
Which layer of the skin is the outermost and avascular?
Signup and view all the answers
The dermis is the thinnest layer of the skin.
The dermis is the thinnest layer of the skin.
Signup and view all the answers
What is the primary function of melanocytes found in the stratum basale?
What is the primary function of melanocytes found in the stratum basale?
Signup and view all the answers
What part of hair penetrates the dermis and subcutaneous layer?
What part of hair penetrates the dermis and subcutaneous layer?
Signup and view all the answers
Gray hair is caused by an increase in the synthesis of melanin.
Gray hair is caused by an increase in the synthesis of melanin.
Signup and view all the answers
The epidermis is composed of keratinized stratified __________ epithelium.
The epidermis is composed of keratinized stratified __________ epithelium.
Signup and view all the answers
What are the three main types of hair found on the human body?
What are the three main types of hair found on the human body?
Signup and view all the answers
Match the skin layers with their characteristics:
Match the skin layers with their characteristics:
Signup and view all the answers
What is the function of hair in the integumentary system?
What is the function of hair in the integumentary system?
Signup and view all the answers
The contraction of the arrector pili muscles causes the hair to stand erect and creates _____ on the skin.
The contraction of the arrector pili muscles causes the hair to stand erect and creates _____ on the skin.
Signup and view all the answers
Psoriasis is characterized by a slower division of keratinocytes.
Psoriasis is characterized by a slower division of keratinocytes.
Signup and view all the answers
Match the type of hair with its description:
Match the type of hair with its description:
Signup and view all the answers
What role does the papilla of the hair play in hair growth?
What role does the papilla of the hair play in hair growth?
Signup and view all the answers
What percentage of body weight does the skin typically represent?
What percentage of body weight does the skin typically represent?
Signup and view all the answers
The process of keratinization begins in the stratum __________.
The process of keratinization begins in the stratum __________.
Signup and view all the answers
Chemotherapy can affect hair growth due to the drugs used in treatment.
Chemotherapy can affect hair growth due to the drugs used in treatment.
Signup and view all the answers
Which of the following structures is NOT considered an accessory structure of the skin?
Which of the following structures is NOT considered an accessory structure of the skin?
Signup and view all the answers
What hormones influence the growth and loss of hair?
What hormones influence the growth and loss of hair?
Signup and view all the answers
What is the primary function of sebaceous glands?
What is the primary function of sebaceous glands?
Signup and view all the answers
Apocrine sweat glands function after birth.
Apocrine sweat glands function after birth.
Signup and view all the answers
What causes acne?
What causes acne?
Signup and view all the answers
The _____ glands secrete a yellowish secretion called cerumen or earwax.
The _____ glands secrete a yellowish secretion called cerumen or earwax.
Signup and view all the answers
Match the type of gland with its correct characteristic:
Match the type of gland with its correct characteristic:
Signup and view all the answers
Which of the following is NOT a function of the integumentary system?
Which of the following is NOT a function of the integumentary system?
Signup and view all the answers
Hirsutism refers to excessive hair growth due to an excess of androgens.
Hirsutism refers to excessive hair growth due to an excess of androgens.
Signup and view all the answers
What is the function of nails?
What is the function of nails?
Signup and view all the answers
Excessive cerumen in the external auditory canal can cause _____ and prevent sound waves from reaching the eardrum.
Excessive cerumen in the external auditory canal can cause _____ and prevent sound waves from reaching the eardrum.
Signup and view all the answers
Which type of sweat gland produces the most sweat on a daily basis?
Which type of sweat gland produces the most sweat on a daily basis?
Signup and view all the answers
What primarily causes basal cell carcinoma?
What primarily causes basal cell carcinoma?
Signup and view all the answers
Melanin production in the skin is decreased by exposure to UV light.
Melanin production in the skin is decreased by exposure to UV light.
Signup and view all the answers
What is the purpose of skin grafting?
What is the purpose of skin grafting?
Signup and view all the answers
The two main regions of the dermis are the __________ and __________ regions.
The two main regions of the dermis are the __________ and __________ regions.
Signup and view all the answers
Match the following types of skin cancers with their descriptions:
Match the following types of skin cancers with their descriptions:
Signup and view all the answers
What condition is characterized by the yellowing of the skin and eyes due to liver disease?
What condition is characterized by the yellowing of the skin and eyes due to liver disease?
Signup and view all the answers
Freckles result from the accumulation of melanin triggered by sunlight exposure.
Freckles result from the accumulation of melanin triggered by sunlight exposure.
Signup and view all the answers
Name the layer of skin that primarily provides strength and elasticity.
Name the layer of skin that primarily provides strength and elasticity.
Signup and view all the answers
The __________ are lines that indicate the predominant direction of collagen fibers in the skin.
The __________ are lines that indicate the predominant direction of collagen fibers in the skin.
Signup and view all the answers
Match the pigments with their roles in skin color.
Match the pigments with their roles in skin color.
Signup and view all the answers
Which of the following is NOT a function of the skin?
Which of the following is NOT a function of the skin?
Signup and view all the answers
Albinism results in an excess of pigment in the skin.
Albinism results in an excess of pigment in the skin.
Signup and view all the answers
What structure in the skin detects external pressure?
What structure in the skin detects external pressure?
Signup and view all the answers
The __________ is also known as the hypodermis, which attaches the skin to underlying tissues and organs.
The __________ is also known as the hypodermis, which attaches the skin to underlying tissues and organs.
Signup and view all the answers
Study Notes
Integumentary System
- The integumentary system is made up of skin, glands, hair, nails, and other associated structures
- It forms a protective barrier, the largest organ of the body in surface area and weight (approximately 2 square meters and 4.5-5kg)
- It plays a crucial role in regulating body temperature and preventing dehydration
- It provides protection from the external environment, protecting from light, heat waves, bacteria, and chemicals.
Skin Structure
- The skin has three main layers: epidermis, dermis, and subcutaneous layer (or hypodermis)
Epidermis
- The outermost layer of the skin, avascular (lacking blood vessels)
- Composed of keratinized stratified squamous epithelium
- Divided into 4-5 layers of cells: stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale
- Stratum corneum - outermost layer; dead, keratinized cells
- Stratum lucidum - translucent layer, only present in thick skin (palms and soles)
- Stratum granulosum - contains keratin and lamellar granules, where keratinization begins
- Stratum spinosum - several layers of keratinocytes
- Stratum basale - deepest layer, closest to the dermis; contains melanocytes and tactile epithelial cells (for sensory reception); Contains stem cells that form new cells
Epidermis Clinical Applications
- Dandruff - excess of keratinized cells shed from the scalp
- Psoriasis - chronic skin disorder characterized by rapid keratinocyte division and movement through the epidermal layers
- Skin cancers - prolonged exposure to UV radiation in sunlight can lead to basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.
- Skin grafts - necessary when stratum basale is destroyed
Dermis
- The middle layer of the skin; rich in blood vessels, nerves, hair follicles, and various glands
- Composed of papillary and reticular regions
- Papillary region - lies just below the epidermis, containing blood vessels, free nerve endings, hair follicles, and touch receptors (Meissner corpuscles)
- Reticular region - consists of dense irregular connective tissue, containing collagen and elastic fibers, adipose cells, hair follicles, sebaceous glands, and sweat glands.
Dermis Clinical Applications
- Striae (stretch marks): rupture of elastic fibers in the dermis, caused by over stretching the skin.
- Lines of cleavage (tension lines): predominant directions of underlying collagen fibers in the dermis; useful for surgeons.
- Fingerprint formation: dermal papillae contours reflected in the epidermal ridges, forming unique fingerprints.
Subcutaneous Layer
- Also called the hypodermis
- Not part of the skin itself
- Attaches the skin to underlying tissues and organs
- Contains blood vessels, nerves (pacinian corpuscles - detect pressure), and fatty tissue (cushioning and insulation)
Sensory Receptors
- The skin contains various sensory receptors to detect different sensations (e.g., touch, pressure, temperature, pain)
- Superficial receptors: Merkel discs, free nerve endings, Meissner corpuscles, and hair root plexuses.
- Deep receptors: Pacinian corpuscles
Skin Color
- Melanin, hemoglobin, and carotene are the main factors influencing skin color.
- Melanin - produced by melanocytes in the stratum basale; determines skin color from pale to black; protects from harmful UV radiation
- Hemoglobin - oxygen-carrying pigment in red blood cells; gives pink/red hue to skin due to blood flow in the dermis.
- Carotenes - yellow-orange pigments found in the stratum corneum, dermis, and subcutaneous layer
Skin Color Clinical Applications
- Freckles - increased melanin concentration in response to sunlight exposure
- Erythema - redness caused by dilated capillaries due to injury, heat, infection, or inflammation.
- Jaundice - yellow discoloration caused by bilirubin buildup; indicative of liver disease.
- Pallor - paleness caused by reduced blood flow, shock, or anemia
- Albinism - congenital disorder characterized by complete or partial absence of pigment in skin, hair and eyes due to an enzyme defect
- Vitiligo - autoimmune disease causing depigmentation patches due to destruction of melanocytes.
- Nevi (moles) - chronic, benign lesions of skin; distinguished from cancerous melanomas.
Tattooing and Body Piercing
- Tattooing - permanent coloration of dermis with foreign pigment using needles.
- Body piercing - insertion of jewelry through the skin using needles; can result in infections, allergic reactions, and anatomical damage (such as nerve or cartilage deformation)
Accessory Structures of the Skin
- Hair
- Sebaceous glands
- Nails
- Sweat glands
Hair
- Shaft - superficial portion
- Root - penetrates the dermis and hypodermis; consists of follicle, matrix (produce new hairs), and associated structures (arrector pili muscles & sebaceous glands)
- Papilla - contains blood vessels that nourish the growing hair
- Hair Growth Cycle - a growing stage and a resting stage; can be affected by various factors (illness, diet, stress, gender)
- Hair Removal - methods like electrolysis
Hair Clinical Applications
- Chemotherapy - hair loss due to drug effects on hair matrix
- Hirsutism - excessive body hair in abnormal amounts in females or prepubertal males
Skin Glands
- Sebaceous glands (oil glands)
- Sudoriferous glands (sweat glands): eccrine and apocrine sweat glands
Sebaceous Glands
- Connected to hair follicles
- Secrete sebum (oil)
- Located in the dermis
- Absent in palms and soles
- Sebum prevents water loss, softens/moistens hairs & skin.
Sudoriferous Glands (Sweat Glands)
- Eccrine & Apocrine sweat glands
- Eccrine sweat glands: widespread throughout the body; regulate body temperature through evaporation; produce sweat, eliminate urea, and activated soon after birth; stimulated by sympathetic nerve signals
- Apocrine sweat glands: located in axilla, pubis, areola; secrete a slightly viscous sweat; become active during sexual excitement and emotional stress causing odor in presence of bacteria.
Ceruminous Glands
- Present in external auditory canal (outer ear canal)
- Secrete cerumen (earwax); which protects from foreign materials, bacteria and fungi.
Nails
- Keratinized plates; composed of tightly packed, hard, and dead epidermis cells
Nail Structure
- Nail body
- Free edge
- Nail root
- Lunula (whitish area)
- Eponychium (cuticle, skin covering base of nail)
- Hyponychium (nail bed at tip of finger)
Nail Function
- Aid in grasping and manipulating small objects
- Protect the ends of the digits
- Produce new nails via cell division of nail matrix
Skin Functions
- Body temperature regulation
- Blood storage
- Protection from the external environment
- Detection of cutaneous sensations
- Excretion of substances
- Synthesis of vitamin D
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on the integumentary system, focusing on skin layers, hair types, and their functions. This quiz covers the structure and characteristics of the skin as well as the role of various components, such as melanocytes and hair follicles. Perfect for biology students and anyone interested in human anatomy.
