p.2
Overview of the Integumentary System
What is the primary component of the integumentary system?
Skin (cutaneous membrane).
p.2
Exocrine Glands: Sebaceous and Sweat Glands
What type of glands are included in the integumentary system?
Sweat glands and sebaceous (oil) glands.
p.2
Overview of the Integumentary System
What are the components of the integumentary system?
Skin, subcutaneous tissue, accessory structures, sweat glands, sebaceous glands, hair, and nails.
p.3
Anatomy of the Skin Layers
What are the two main layers of human skin?
Epidermis (outermost) and dermis (innermost).
p.3
Anatomy of the Skin Layers
What separates the epidermis and dermis?
The basement membrane (BM).
p.2
Accessory Structures of the Skin
What are the accessory structures of the integumentary system?
Sweat glands, sebaceous (oil) glands, hair, and nails.
p.1
Overview of the Integumentary System
What is the focus of Lecture 2 in Human Anatomy?
The Integumentary System.
p.21
Anatomy of the Skin Layers
What is the Stratum Basale?
The deepest layer of the epidermis, closest to the dermis.
p.7
Body Temperature Regulation
What process occurs when sweat evaporates?
Water changes from liquid to vapor, and heat is lost.
p.33
Anatomy of the Skin Layers
What are glycosaminoglycans found in the ground substance?
Hyaluronic acid, chondroitin sulfate, and dermatan sulfate.
p.34
Anatomy of the Skin Layers
What is another name for the hypodermis?
Subcutaneous tissue or superficial fascia.
p.36
Accessory Structures of the Skin
What are the accessory organs of the skin?
Hair, skin glands, and nails.
p.14
Anatomy of the Skin Layers
What type of tissue is the epidermis composed of?
Stratified squamous epithelium.
p.28
Anatomy of the Skin Layers
What is the stratum corneum?
The outermost layer of the epidermis, closest to the surface.
p.45
Exocrine Glands: Sebaceous and Sweat Glands
What type of glands are ceruminous glands?
Modified apocrine sweat glands.
p.48
Functions of the Skin
What social interactions can be influenced by the integumentary system?
Facial expressions, blushing, touching, etc.
p.25
Anatomy of the Skin Layers
How many layers of cells does the Stratum Granulosum consist of in thick skin?
A few layers of flattened cells.
p.49
Interactions with Other Organ Systems
How does the skin interact with the immune system?
The skin serves as a physical barrier to microorganisms, defending the body from pathogens.
p.9
Skin Conditions: Pimples and Wrinkles
What causes pimples (acne)?
A build-up of dirt and oils.
p.35
Anatomy of the Skin Layers
What is the primary function of the hypodermis?
To attach the dermis to its underlying tissues.
p.29
Anatomy of the Skin Layers
What are the main components of the dermis?
Connective tissue, blood vessels, and nerve endings.
What is one of the major functions of the skin related to temperature?
Regulate body temperature.
p.26
Anatomy of the Skin Layers
Can the Stratum lucidum be identified in thin skin?
No, it can usually not be identified.
p.24
Anatomy of the Skin Layers
What separates the cells in the Stratum Spinosum?
Narrow, translucent clefts.
p.12
Anatomy of the Skin Layers
What layer is the dermis anchored to?
Subcutaneous layer (Hypodermis).
What types of stimuli can the skin receive?
Touch, pain, temperature change, etc.
What is the role of Vitamin D in the body?
It aids in the absorption of calcium into the blood.
p.25
Anatomy of the Skin Layers
What is the Stratum Granulosum?
The third layer of the skin.
p.46
Functions of the Skin
What is one of the primary functions of the skin?
Protection, providing a barrier to fluid loss from the body.
p.49
Interactions with Other Organ Systems
What role does the skin play in vitamin D synthesis?
The skin synthesizes vitamin D, which is needed by the digestive system to absorb calcium from food.
p.46
Functions of the Skin
How does intact skin contribute to barrier function?
It prevents the entry of microorganisms into the body.
p.49
Interactions with Other Organ Systems
How does the skin help regulate body temperature?
The skin works with the cardiovascular system to lose or conserve body heat through vasodilation or vasoconstriction.
p.49
Interactions with Other Organ Systems
What system depends on nerve receptors in the skin?
The nervous system depends on nerve receptors in the skin to detect certain sensations from the outside world.
p.37
Accessory Structures of the Skin
Is it true that most of the human skin is hairless?
No, most of the skin is haired, but the hair is short, fine, and lightly pigmented.
p.47
Functions of the Skin
What substances can the skin excrete?
Water, salt, and small amounts of waste products such as urea.
p.10
Skin Conditions: Pimples and Wrinkles
How do clogged pores contribute to pimples?
Clogged pores trap oil and bacteria, leading to inflammation.
p.47
Skin Protection and Barrier Functions
What role do melanocytes play in skin protection?
They contain melanin, which absorbs UV radiation and distributes pigment to neighboring cells.
p.14
Anatomy of the Skin Layers
How do oxygen and nutrients reach the epidermis?
They diffuse from the underlying dermis.
p.54
Overview of the Integumentary System
What is the Rule of Nines used for?
To estimate the total body surface area affected by burns.
p.21
Anatomy of the Skin Layers
What do basal cells in the Stratum Basale represent?
The stem cells of the epidermis.
p.28
Anatomy of the Skin Layers
What proportion of the epidermal thickness does the stratum corneum make up?
Three fourths of the epidermal thickness.
p.24
Anatomy of the Skin Layers
What is the significance of the spine-like extensions in the Stratum Spinosum?
They interconnect the cells of this layer.
p.44
Exocrine Glands: Sebaceous and Sweat Glands
Where can the secretory portion of eccrine glands be located?
In the dermis or in the hypodermis.
p.17
Anatomy of the Skin Layers
What is the deepest layer of the epidermis called?
Stratum Basale (Germinativum).
p.7
Body Temperature Regulation
What happens to blood vessels in the dermis when body temperature rises?
They dilate, increasing blood flow.
p.7
Body Temperature Regulation
How does the body lose heat when temperature rises?
By radiation as blood flow increases.
p.43
Exocrine Glands: Sebaceous and Sweat Glands
What are sebaceous glands?
Simple branched areolar glands that secrete sebum.
p.12
Anatomy of the Skin Layers
What type of tissue composes the epidermis?
Stratified squamous epithelium.
p.43
Exocrine Glands: Sebaceous and Sweat Glands
What is sebum?
An oily product secreted by sebaceous glands.
p.27
Anatomy of the Skin Layers
Why are individual cells in the Stratum Corneum difficult to observe?
Because nuclei can no longer be identified, the cells are very flat, and the space between cells is filled with lipids.
p.28
Anatomy of the Skin Layers
What happens to cells in the stratum corneum?
Cells are constantly shed from this part.
p.24
Anatomy of the Skin Layers
What are the cytoplasmic extensions in the Stratum Spinosum called?
Spine-like cytoplasmic extensions.
p.39
Accessory Structures of the Skin
What are terminal hairs?
Hairs found in parts of the skin perceived as 'hairy'.
What role does the skin play in immunity?
It contributes to the body's immune response.
p.56
Functions of the Skin
What happens to your hair when you are frightened or cold?
It stands on end and you develop 'goose bumps'.
p.5
Overview of the Integumentary System
How quickly does the skin regenerate?
It is the fastest organ to regenerate.
p.26
Anatomy of the Skin Layers
What happens to the nuclei in the outer part of the stratum granulosum?
They begin to degenerate.
p.10
Skin Conditions: Pimples and Wrinkles
What is a primary cause of pimples?
Excess oil production in the skin.
How is Vitamin D synthesized in the skin?
Through exposure to sunlight.
p.14
Anatomy of the Skin Layers
Is the epidermis vascular or avascular?
Avascular, as it has no blood supply of its own.
p.28
Anatomy of the Skin Layers
What is the appearance of the stratum corneum?
It has a somewhat looser appearance.
p.29
Body Temperature Regulation
How does the dermis contribute to temperature regulation?
Through blood vessel dilation and constriction.
p.42
Accessory Structures of the Skin
What is the cuticle?
A fold of stratum corneum on the proximal end of the nail.
p.18
Anatomy of the Skin Layers
What is the deepest layer of the epidermis called?
Stratum Basale (Germinativum).
p.40
Anatomy of the Skin Layers
What is gray hair a mixture of?
Pigmented and non-pigmented hairs.
p.48
Overview of the Integumentary System
What types of receptors are well-supplied in the integumentary system?
Receptors for touch, pain, temperature, vibration, and pressure.
p.27
Anatomy of the Skin Layers
What is the Stratum Corneum?
The final layer of the epidermis.
p.30
Anatomy of the Skin Layers
What type of tissue primarily composes the dermis?
Dense fibrous connective tissue.
p.17
Anatomy of the Skin Layers
What type of epithelium is the epidermis?
Keratinized stratified squamous epithelium.
p.21
Anatomy of the Skin Layers
What type of cells make up the Stratum Basale?
A single layer of columnar or cuboidal cells.
p.36
Accessory Structures of the Skin
What is the primary function of nails?
To protect the tips of fingers and toes and assist in grasping.
p.54
Overview of the Integumentary System
How is the body divided in the Rule of Nines for adults?
The body is divided into sections, each representing approximately 9% of total body surface area.
p.30
Anatomy of the Skin Layers
What types of fibers are abundant in the dermis?
Collagenous and elastic fibers.
p.40
Anatomy of the Skin Layers
What determines hair color?
The amount and type of melanin present.
p.51
Skin Conditions: Pimples and Wrinkles
What distinguishes a second-degree burn from a first-degree burn?
Second-degree burns may be erythematous or whitish with a fibrinous exudate, commonly have blisters, and the wound base is sensitive and painful.
p.39
Accessory Structures of the Skin
How does the arrector pili muscle affect hair?
It makes your hair stand up on its end.
p.42
Accessory Structures of the Skin
What are nails composed of?
Plates of stratified squamous epithelial cells with hard keratin.
p.34
Functions of the Skin
What are two main functions of the hypodermis?
Energy reservoir and thermal insulation.
p.29
Functions of the Skin
What functions does the dermis serve?
Provides strength, elasticity, and houses various structures like hair follicles and glands.
p.29
Anatomy of the Skin Layers
What type of cells are primarily found in the dermis?
Fibroblasts, which produce collagen and elastin.
p.7
Body Temperature Regulation
What happens to blood vessels in the skin when you are cold?
They constrict to conserve heat.
p.23
Anatomy of the Skin Layers
What is keratin?
A tough protein deposited within the cell.
p.21
Anatomy of the Skin Layers
What is the role of mitotic activity in the Stratum Basale?
It replenishes cells in more superficial layers as they are shed.
p.43
Exocrine Glands: Sebaceous and Sweat Glands
What is vernix caseosa?
A white covering on a fetus.
p.56
Functions of the Skin
What causes goose bumps?
Tiny muscles attached to hair follicles contract.
p.44
Exocrine Glands: Sebaceous and Sweat Glands
How do the secretions of apocrine glands compare to those of eccrine glands?
Apocrine gland secretions are more viscous.
p.5
Anatomy of the Skin Layers
What is the typical thickness range of most skin?
1 – 2 mm, but can range from 0.5 – 6 mm.
p.26
Anatomy of the Skin Layers
What is the Stratum lucidum?
The fourth layer of the skin consisting of several layers of flattened dead cells.
p.37
Accessory Structures of the Skin
Which areas of the body are truly hairless?
The palms of hands, soles of feet, distal phalanges, sides of fingers and toes, and parts of the external genitalia.
p.19
Anatomy of the Skin Layers
What is the primary function of keratinocytes?
Waterproofing and protecting the skin, nails, and hair.
p.26
Anatomy of the Skin Layers
What is visible in the cells of the Stratum lucidum?
Faint nuclear outlines in only a few of the cells.
p.30
Anatomy of the Skin Layers
How does the thickness of the dermis compare to the epidermis?
The dermis is much thicker than the epidermis.
p.47
Skin Conditions: Pimples and Wrinkles
What happens to skin exposed to sunlight over time?
It becomes wrinkled and creased due to disruption of collagen and elastin in the dermis.
p.47
Skin Conditions: Pimples and Wrinkles
What causes the changes in skin texture due to sun exposure?
Loss of fibroblasts which make new proteins.
p.12
Accessory Structures of the Skin
What are the integumentary glands responsible for?
Producing sweat, oil, etc.
p.46
Functions of the Skin
Where are new epidermal cells produced?
In the deepest layer of the epidermis.
p.46
Functions of the Skin
What happens to epidermal cells as they age?
They gradually migrate towards the surface and wear off.
p.44
Functions of the Skin
What is the primary function of eccrine glands?
To produce sweat, which helps regulate body temperature.
p.40
Anatomy of the Skin Layers
What determines hair texture?
The shape of the hair shaft.
p.13
Anatomy of the Skin Layers
What is the function of the hypodermis?
To insulate the body and absorb shock.
p.53
Overview of the Integumentary System
What does TBSA stand for in burn assessment?
Total percentage of body surface area.
p.9
Skin Conditions: Pimples and Wrinkles
What leads to the formation of wrinkles?
Decreased elasticity with age and reduced oil production, leading to dryness.
p.37
Accessory Structures of the Skin
What is a characteristic feature of human skin regarding hair?
The apparent lack of hair on most of the body surface.
p.45
Exocrine Glands: Sebaceous and Sweat Glands
What type of glands are mammary glands?
Modified apocrine sweat glands.
p.33
Anatomy of the Skin Layers
What do fibroblasts synthesize?
Collagen, elastin, and reticulin.
p.36
Accessory Structures of the Skin
What role do skin glands play in the integumentary system?
They help in secretion and regulation of body functions.
p.33
Anatomy of the Skin Layers
What is the role of collagen and reticulin in the skin?
They provide tensile strength.
p.42
Accessory Structures of the Skin
What do nails protect?
The distal ends of phalanges.
p.34
Exocrine Glands: Sebaceous and Sweat Glands
Why are hypodermic injections administered into the hypodermis?
Because it is highly vascular.
p.33
Anatomy of the Skin Layers
What do elastic fibers do in the skin?
They allow for restoration of shape after deformation.
p.10
Skin Conditions: Pimples and Wrinkles
What role do hormones play in the development of pimples?
Hormonal changes can increase oil production, leading to pimples.
p.43
Exocrine Glands: Sebaceous and Sweat Glands
What are the functions of sebum?
Helps prevent hair from becoming brittle, reduces water evaporation from the skin, keeps skin soft, and contains a bactericidal agent.
p.46
Functions of the Skin
What role do antimicrobial proteins play in the skin?
They pierce holes in the outer membranes of microorganisms.
p.27
Anatomy of the Skin Layers
What role do lipids play in the Stratum Corneum?
They cement the cells together into a continuous membrane.
p.46
Functions of the Skin
How does the skin resist wear and tear?
Through continuous replacement of outer epidermal cells.
p.49
Interactions with Other Organ Systems
What is the overall role of the skin in maintaining homeostasis?
The skin works with other organ systems to maintain homeostasis.
p.10
Skin Conditions: Pimples and Wrinkles
What dietary factors can influence the occurrence of pimples?
Certain foods, like dairy and high-glycemic-index foods, may trigger pimples.
p.44
Functions of the Skin
What does sweat consist of?
A watery mixture of salts, antibodies, and metabolic wastes.
p.51
Skin Conditions: Pimples and Wrinkles
What is a key feature of a fourth-degree burn?
It involves deep tissues including fascia.
p.36
Accessory Structures of the Skin
What is the function of hair in the integumentary system?
Provides protection, regulates body temperature, and enhances sensation.
How does the skin protect the body?
By protecting underlying tissue.
p.10
Skin Conditions: Pimples and Wrinkles
How can bacteria contribute to the formation of pimples?
Bacteria can multiply in clogged pores, causing infection and inflammation.
p.44
Exocrine Glands: Sebaceous and Sweat Glands
What are the two principal types of sweat glands?
Eccrine and apocrine glands.
p.40
Anatomy of the Skin Layers
What causes red hair?
A modified type of melanin that contains iron.
p.44
Exocrine Glands: Sebaceous and Sweat Glands
Where are apocrine glands mainly found?
In the skin of the armpits, anogenital areas, and areola of the breasts.
p.33
Anatomy of the Skin Layers
What types of cells are involved in the cellular structure of the skin?
Fibroblasts, histiocytes, endothelial cells, macrophages, dendritic cells, mast cells, smooth muscle cells, and peripheral nerve cells.
p.23
Anatomy of the Skin Layers
What effect does keratin have on skin cells as they move outward?
It hardens and flattens the cells and waterproofs the skin.
p.51
Skin Conditions: Pimples and Wrinkles
What are the characteristics of a first-degree burn?
Red, erythematous, very sensitive to touch, very painful, usually moist, and no blisters.
p.39
Accessory Structures of the Skin
What is the arrector pili muscle?
A bundle of smooth muscle associated with each hair follicle.
p.43
Exocrine Glands: Sebaceous and Sweat Glands
Where are sebaceous glands located?
Scattered all over the skin except in the palms, soles, and sides of the feet.
p.21
Anatomy of the Skin Layers
Where do the cells of the Stratum Basale rest?
On the basement membrane.
p.13
Anatomy of the Skin Layers
What are the main layers of the skin?
Epidermis, dermis, and hypodermis.
p.39
Anatomy of the Skin Layers
Where is the root of each hair anchored?
In a tubular invagination of the epidermis called the hair follicle.
p.39
Anatomy of the Skin Layers
What is the hair follicle's relationship to the dermis and hypodermis?
It extends down into the dermis and usually a short distance into the hypodermis.
p.28
Skin Protection and Barrier Functions
How does the stratum corneum contribute to body protection?
It provides protection due to its functional features.
p.10
Skin Conditions: Pimples and Wrinkles
How does stress affect pimples?
Stress can lead to hormonal changes that increase oil production.
How is metabolism related to the skin?
The skin is involved in metabolic processes.
p.51
Skin Conditions: Pimples and Wrinkles
What are the characteristics of a third-degree burn?
Surface may be white, black, leathery, pale, or bright red; generally anesthetic or hypoesthetic; subdermal vessels do not blanch; no blisters; hair easily pulled from its follicle.
p.13
Anatomy of the Skin Layers
What are the main components of the dermis?
Collagen, elastin, and connective tissue.
p.40
Anatomy of the Skin Layers
What do perms do to hair shafts?
Use chemicals to flatten shafts and make hair curly.
p.5
Overview of the Integumentary System
What is the average surface area of the skin?
About 3000 square inches.
