The integumentary system consists of the skin, hair, nails, and glands. The skin has three layers - the epidermis, dermis, and hypodermis. The epidermis is made of stratified squamous epithelium and regenerates every 28 days. It contains melanocytes which produce melanin and keratinocytes which produce keratin. The dermis contains blood vessels, hair follicles, and glands. The hypodermis is made of loose connective tissue and fat cells. Skin color is determined by melanin, carotene, and hemoglobin. Appendages include sebaceous glands, sweat glands, hair, hair follicles, and nails.
The integumentary system includes the skin, hair, nails, and exocrine glands. The skin is composed of two main layers - the epidermis and dermis. The epidermis is made of stratified squamous epithelium and provides protection against pathogens and moisture loss. It undergoes constant renewal through mitosis in the basal layer. The dermis contains collagen, elastic fibers, and vasculature that provide strength and nourishment to the skin. Accessory structures such as hair, nails, and exocrine glands contribute additional protective and sensory functions.
The integumentary system includes the skin, hair, nails, and exocrine glands. The skin is composed of two main layers - the epidermis and dermis. The epidermis is made of stratified squamous epithelium and provides protection against pathogens and moisture loss. It undergoes constant renewal through mitosis in the basal layer. The dermis contains collagen, elastic fibers, and vasculature that provide strength and nourishment to the skin. Accessory structures such as hair, nails, and exocrine glands contribute additional protective and sensory functions.
The integumentary system includes the skin, hair, nails, and exocrine glands. The skin is composed of two main layers - the epidermis and dermis. The epidermis is made of stratified squamous epithelium without blood vessels and contains five layers including the basal and stratum corneum layers. Below the epidermis, the dermis contains connective tissue, blood vessels, hair follicles, and sebaceous and sweat glands. Accessory structures of the skin include hair, nails, and exocrine glands that secrete sebum from sebaceous glands or sweat from eccrine and apocrine sweat glands. The integumentary system acts as a
The document provides an overview of the integumentary system, including the layers of the skin (epidermis and dermis), accessory structures like hair, glands, and nails. It describes the cell types and layers within the epidermis, including basal, spinous, granular, and corneum layers. It also discusses pigmentation from melanin and other sources, as well as diseases and disorders that can affect the integumentary system like skin cancer, jaundice, and vitiligo.
The document discusses the anatomy and functions of the integumentary system. It describes the two main layers of skin - the epidermis and dermis. The dermis contains blood vessels, hair follicles, sweat and sebaceous glands. The dermis regulates body temperature through blood vessel dilation and constriction. Keratinization occurs as cells move from the stratum basale to the stratum corneum. The skin protects the body, regulates temperature and sensation, and produces Vitamin D.
The skin has three layers - the epidermis, dermis, and subcutaneous tissue. The epidermis is made of stratified squamous epithelium and contains keratinocytes that produce keratin, and melanocytes that produce melanin pigment. The dermis lies below the epidermis and contains collagen, elastic fibers, and sensory receptors. The deepest layer, the subcutaneous tissue, contains fat and connective tissue. Skin has appendages like hair follicles, sebaceous glands, sweat glands, and nails. The skin acts as a barrier and regulates body temperature, and contains sensory receptors for touch, pressure, and temperature.
The document summarizes the key structures and functions of the integumentary system in 3 paragraphs or less:
The integumentary system includes the skin, hair, and nails. The skin is the largest organ and protects the body from damage, regulates temperature, and detects sensations. It is composed of three layers - the epidermis, dermis, and hypodermis. The epidermis contains keratinocytes and other cell types and becomes keratinized to form a protective barrier. Hair grows from follicles in the dermis and comes in different types. Glands in the skin including sweat glands help regulate temperature and sebaceous glands produce oil to moisturize the skin.
The document discusses the structure and functions of the integumentary system. It describes the layers of the epidermis and dermis, including the cells found in each layer. The main functions of the skin are protection, regulation of body temperature, sensation, and synthesis of vitamin D. Common disorders mentioned include burns, skin cancer, and imbalances in skin pigmentation.
The integumentary system includes the skin, hair, nails, and exocrine glands. The skin is composed of two main layers - the epidermis and dermis. The epidermis is made of stratified squamous epithelium and provides protection against pathogens and moisture loss. It undergoes constant renewal through mitosis in the basal layer. The dermis contains collagen, elastic fibers, and vasculature that provide strength and nourishment to the skin. Accessory structures such as hair, nails, and exocrine glands contribute additional protective and sensory functions.
The integumentary system includes the skin, hair, nails, and exocrine glands. The skin is composed of two main layers - the epidermis and dermis. The epidermis is made of stratified squamous epithelium and provides protection against pathogens and moisture loss. It undergoes constant renewal through mitosis in the basal layer. The dermis contains collagen, elastic fibers, and vasculature that provide strength and nourishment to the skin. Accessory structures such as hair, nails, and exocrine glands contribute additional protective and sensory functions.
The integumentary system includes the skin, hair, nails, and exocrine glands. The skin is composed of two main layers - the epidermis and dermis. The epidermis is made of stratified squamous epithelium without blood vessels and contains five layers including the basal and stratum corneum layers. Below the epidermis, the dermis contains connective tissue, blood vessels, hair follicles, and sebaceous and sweat glands. Accessory structures of the skin include hair, nails, and exocrine glands that secrete sebum from sebaceous glands or sweat from eccrine and apocrine sweat glands. The integumentary system acts as a
The document provides an overview of the integumentary system, including the layers of the skin (epidermis and dermis), accessory structures like hair, glands, and nails. It describes the cell types and layers within the epidermis, including basal, spinous, granular, and corneum layers. It also discusses pigmentation from melanin and other sources, as well as diseases and disorders that can affect the integumentary system like skin cancer, jaundice, and vitiligo.
The document discusses the anatomy and functions of the integumentary system. It describes the two main layers of skin - the epidermis and dermis. The dermis contains blood vessels, hair follicles, sweat and sebaceous glands. The dermis regulates body temperature through blood vessel dilation and constriction. Keratinization occurs as cells move from the stratum basale to the stratum corneum. The skin protects the body, regulates temperature and sensation, and produces Vitamin D.
The skin has three layers - the epidermis, dermis, and subcutaneous tissue. The epidermis is made of stratified squamous epithelium and contains keratinocytes that produce keratin, and melanocytes that produce melanin pigment. The dermis lies below the epidermis and contains collagen, elastic fibers, and sensory receptors. The deepest layer, the subcutaneous tissue, contains fat and connective tissue. Skin has appendages like hair follicles, sebaceous glands, sweat glands, and nails. The skin acts as a barrier and regulates body temperature, and contains sensory receptors for touch, pressure, and temperature.
The document summarizes the key structures and functions of the integumentary system in 3 paragraphs or less:
The integumentary system includes the skin, hair, and nails. The skin is the largest organ and protects the body from damage, regulates temperature, and detects sensations. It is composed of three layers - the epidermis, dermis, and hypodermis. The epidermis contains keratinocytes and other cell types and becomes keratinized to form a protective barrier. Hair grows from follicles in the dermis and comes in different types. Glands in the skin including sweat glands help regulate temperature and sebaceous glands produce oil to moisturize the skin.
The document discusses the structure and functions of the integumentary system. It describes the layers of the epidermis and dermis, including the cells found in each layer. The main functions of the skin are protection, regulation of body temperature, sensation, and synthesis of vitamin D. Common disorders mentioned include burns, skin cancer, and imbalances in skin pigmentation.
The document summarizes the key functions and layers of the integumentary system. It discusses the epidermis and dermis layers of skin and describes their composition and roles in protection, sensation, and insulation. It also outlines the major accessory structures of skin including hair, nails, and exocrine glands like sweat and sebaceous glands, and their functions in thermoregulation, nourishment, and defense against pathogens.
5. The Integument and Related StructuresSUNY Ulster
The document summarizes the key structures and functions of the integumentary system including the epidermis, dermis, hypodermis, hair follicles, glands, and related structures like hooves and horns. It describes the cell types in the epidermis and its layers, the components and layers of the dermis, and structures in the hypodermis. It also discusses hair growth cycles, pigmentation, specialized structures like paw pads, and the types and functions of glands and other skin derivatives.
The integumentary system consists of the skin and its accessory structures. The skin is made up of three main layers - the epidermis, dermis and hypodermis. The epidermis is the outermost layer and provides protection from pathogens and environmental damage. Below the epidermis is the dermis, which contains blood vessels, hair follicles and glands. The deepest layer is the hypodermis, comprising connective tissue and fat. In addition to protection, the skin regulates temperature and synthesizes vitamin D. Accessory structures include hair, nails, sweat and sebaceous glands. Skin disorders include wounds, burns and skin cancers like basal cell carcinoma and melanoma.
Body membranes line body cavities and surfaces, and fall into two groups: epithelial and connective tissue membranes. Epithelial membranes include the cutaneous, mucous, and serous membranes which contain an epithelial sheet and underlying connective tissue. The skin is the cutaneous membrane and functions to protect the body, regulate temperature, and synthesize vitamin D. The skin has an outer epidermis and deeper dermis layer. Skin appendages like hair, nails, and glands aid homeostasis. Imbalances can include infections and allergies of the skin.
The integumentary system consists of the skin and its appendages. The skin is made up of two layers - the epidermis and dermis. The epidermis is avascular and composed of stratified squamous epithelium in five layers. The dermis lies below and contains blood vessels, hair follicles, and glands. Functions of the skin include protection, regulation of temperature and moisture, synthesis of vitamin D, and sensation. Sweat glands and sebaceous glands are important appendages that aid temperature regulation and protect the skin surface.
This document discusses the classification and structure of the skin and other body membranes. It covers the three main types of membranes - epithelial, serous, and synovial membranes. It then describes the layers and structures of the skin in detail, including the epidermis, dermis, glands, hair follicles and nails. It discusses skin color and conditions like sun exposure, bruising and jaundice. Finally, it briefly outlines some common skin disorders and conditions.
The integumentary system consists of the skin, hair, nails, sweat glands and oil glands. The skin has two main layers - the epidermis and dermis. The epidermis is made of stratified squamous epithelium and provides protective, regulatory and sensory functions. It consists of several layers of keratinocytes. The dermis lies below the epidermis and contains connective tissue, hair follicles, sweat and sebaceous glands. Skin appendages like hair, nails, sweat and oil glands develop from the epidermis. The skin regulates body temperature, protects from damage and pathogens, and detects sensations like touch and pressure.
Skin structures and functions ppt Dr.MumuxMumux Mirani
The skin is the largest organ of the body and consists of three layers - the epidermis, dermis and subcutaneous layer. The epidermis is made up of keratinocytes, melanocytes, Merkel cells and Langerhans cells arranged in five layers. The dermis lies below the epidermis and contains hair follicles, sweat and sebaceous glands, nerves and blood vessels. The subcutaneous layer is made of fat and connective tissue. The skin acts as a protective barrier, regulates body temperature, maintains fluid and electrolyte balance, acts as a blood reservoir and sensory organ, synthesizes vitamin D, and contributes to self-image.
The integumentary system includes the skin, hair, nails, and glands. The skin is the largest organ and protects the body. It has two main layers - the epidermis composed of keratinized cells, and the dermis of connective tissue. The epidermis contains melanocytes, Langerhans cells, and Merkel cells. Hair, sebaceous glands, sweat glands, and nails are structures within the skin. The skin regulates temperature, protects, and has sensory functions.
The document provides an overview of the integumentary system, including the structure and function of the skin and its accessory structures. It describes the three main layers of the skin - epidermis, dermis and subcutaneous layer - and their cellular composition. The epidermis contains keratinocytes, melanocytes, Langerhans cells and Merkel cells. The dermis lies underneath and contains collagen, elastic fibers and structures like hair follicles and sweat glands. The subcutaneous layer attaches the skin to underlying tissues. Accessory structures include hair, nails and various glands. The document also discusses skin color, wound healing, development and aging of the integumentary system.
The integumentary system comprises the skin and its appendages. It protects the body from damage and regulates temperature. The skin has three layers - epidermis, dermis and subcutaneous tissue. The epidermis contains keratinocytes, melanocytes, Langerhans cells and Merkel cells. Hair, nails, sebaceous glands and sweat glands are skin appendages. Melanin pigment determines skin color. The integumentary system acts as a barrier and plays roles in sensation, temperature regulation and vitamin D synthesis.
This document provides an overview of the structure and functions of the skin and its appendages. It notes that the skin is the largest organ and is composed of three main layers - the epidermis, dermis and hypodermis. The epidermis provides protection and waterproofing and has several layers including the stratum basale, stratum spinosum, stratum granulosum and stratum corneum. The dermis lies underneath and contains blood vessels, nerves and connective tissue. The deepest layer, the hypodermis, stores fat and anchors the skin. The document also describes skin appendages like hair, sebaceous glands, sweat glands and nails, and their structure and functions.
The document provides an overview of the integumentary system, including its structure, functions, and clinical applications. It describes the layers of the skin, hair and nails, and discusses pigmentation. Conditions like infections, tumors, injuries, and disorders are explained. Careers like dermatology are also mentioned. Medical procedures for the skin like grafts, artificial skin, and transdermal medications are highlighted.
The document provides an overview of the structure and functions of the integumentary system. It describes the layers of the skin, including the epidermis and dermis. It outlines the principal cells of the epidermis and layers of the epidermis. It also discusses the structure and regions of the dermis, skin pigmentation, accessory structures like hair and glands, and the functions of the skin like protection and thermoregulation. Finally, it covers wound healing, scar formation, and age-related changes to the skin.
Training presentation for a company who has employed the parallel import strategy of importing their cosmetivs. Since they do not have the resources of the local agents, I have been commissioned to accummulate all information pertaining to their stocked products and supply a fully comprehensive training presentation.
The document discusses the structure and function of the integumentary system, specifically the skin. It describes the three main layers of skin - the epidermis, dermis and hypodermis. The epidermis contains keratinocytes, melanocytes, Langerhans cells and Merkel cells. It has several layers with different functions. The dermis contains collagen, elastic fibers, blood vessels and glands. It is made up of papillary and reticular layers. The hypodermis contains fat and connective tissue. Skin color is determined by melanin, hemoglobin and carotene. Hair, nails and glands are important accessory structures of the skin.
Skin is the largest organ or outer protective covering of body. It is composed of three layers: epidermis, dermis or subcutaneous tissues.
Skin is the body's defense covering, which protects against heat, light, injury and infection.
The skin is the largest organ of the body, with a total area of about 20 square feet. ... Skin has three layers: The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone. The dermis, beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands.
The document summarizes the key functions and layers of the integumentary system. It discusses the epidermis and dermis layers of skin and describes their composition and roles in protection, sensation, and insulation. It also outlines the major accessory structures of skin including hair, nails, and exocrine glands like sweat and sebaceous glands, and their functions in thermoregulation, nourishment, and defense against pathogens.
5. The Integument and Related StructuresSUNY Ulster
The document summarizes the key structures and functions of the integumentary system including the epidermis, dermis, hypodermis, hair follicles, glands, and related structures like hooves and horns. It describes the cell types in the epidermis and its layers, the components and layers of the dermis, and structures in the hypodermis. It also discusses hair growth cycles, pigmentation, specialized structures like paw pads, and the types and functions of glands and other skin derivatives.
The integumentary system consists of the skin and its accessory structures. The skin is made up of three main layers - the epidermis, dermis and hypodermis. The epidermis is the outermost layer and provides protection from pathogens and environmental damage. Below the epidermis is the dermis, which contains blood vessels, hair follicles and glands. The deepest layer is the hypodermis, comprising connective tissue and fat. In addition to protection, the skin regulates temperature and synthesizes vitamin D. Accessory structures include hair, nails, sweat and sebaceous glands. Skin disorders include wounds, burns and skin cancers like basal cell carcinoma and melanoma.
Body membranes line body cavities and surfaces, and fall into two groups: epithelial and connective tissue membranes. Epithelial membranes include the cutaneous, mucous, and serous membranes which contain an epithelial sheet and underlying connective tissue. The skin is the cutaneous membrane and functions to protect the body, regulate temperature, and synthesize vitamin D. The skin has an outer epidermis and deeper dermis layer. Skin appendages like hair, nails, and glands aid homeostasis. Imbalances can include infections and allergies of the skin.
The integumentary system consists of the skin and its appendages. The skin is made up of two layers - the epidermis and dermis. The epidermis is avascular and composed of stratified squamous epithelium in five layers. The dermis lies below and contains blood vessels, hair follicles, and glands. Functions of the skin include protection, regulation of temperature and moisture, synthesis of vitamin D, and sensation. Sweat glands and sebaceous glands are important appendages that aid temperature regulation and protect the skin surface.
This document discusses the classification and structure of the skin and other body membranes. It covers the three main types of membranes - epithelial, serous, and synovial membranes. It then describes the layers and structures of the skin in detail, including the epidermis, dermis, glands, hair follicles and nails. It discusses skin color and conditions like sun exposure, bruising and jaundice. Finally, it briefly outlines some common skin disorders and conditions.
The integumentary system consists of the skin, hair, nails, sweat glands and oil glands. The skin has two main layers - the epidermis and dermis. The epidermis is made of stratified squamous epithelium and provides protective, regulatory and sensory functions. It consists of several layers of keratinocytes. The dermis lies below the epidermis and contains connective tissue, hair follicles, sweat and sebaceous glands. Skin appendages like hair, nails, sweat and oil glands develop from the epidermis. The skin regulates body temperature, protects from damage and pathogens, and detects sensations like touch and pressure.
Skin structures and functions ppt Dr.MumuxMumux Mirani
The skin is the largest organ of the body and consists of three layers - the epidermis, dermis and subcutaneous layer. The epidermis is made up of keratinocytes, melanocytes, Merkel cells and Langerhans cells arranged in five layers. The dermis lies below the epidermis and contains hair follicles, sweat and sebaceous glands, nerves and blood vessels. The subcutaneous layer is made of fat and connective tissue. The skin acts as a protective barrier, regulates body temperature, maintains fluid and electrolyte balance, acts as a blood reservoir and sensory organ, synthesizes vitamin D, and contributes to self-image.
The integumentary system includes the skin, hair, nails, and glands. The skin is the largest organ and protects the body. It has two main layers - the epidermis composed of keratinized cells, and the dermis of connective tissue. The epidermis contains melanocytes, Langerhans cells, and Merkel cells. Hair, sebaceous glands, sweat glands, and nails are structures within the skin. The skin regulates temperature, protects, and has sensory functions.
The document provides an overview of the integumentary system, including the structure and function of the skin and its accessory structures. It describes the three main layers of the skin - epidermis, dermis and subcutaneous layer - and their cellular composition. The epidermis contains keratinocytes, melanocytes, Langerhans cells and Merkel cells. The dermis lies underneath and contains collagen, elastic fibers and structures like hair follicles and sweat glands. The subcutaneous layer attaches the skin to underlying tissues. Accessory structures include hair, nails and various glands. The document also discusses skin color, wound healing, development and aging of the integumentary system.
The integumentary system comprises the skin and its appendages. It protects the body from damage and regulates temperature. The skin has three layers - epidermis, dermis and subcutaneous tissue. The epidermis contains keratinocytes, melanocytes, Langerhans cells and Merkel cells. Hair, nails, sebaceous glands and sweat glands are skin appendages. Melanin pigment determines skin color. The integumentary system acts as a barrier and plays roles in sensation, temperature regulation and vitamin D synthesis.
This document provides an overview of the structure and functions of the skin and its appendages. It notes that the skin is the largest organ and is composed of three main layers - the epidermis, dermis and hypodermis. The epidermis provides protection and waterproofing and has several layers including the stratum basale, stratum spinosum, stratum granulosum and stratum corneum. The dermis lies underneath and contains blood vessels, nerves and connective tissue. The deepest layer, the hypodermis, stores fat and anchors the skin. The document also describes skin appendages like hair, sebaceous glands, sweat glands and nails, and their structure and functions.
The document provides an overview of the integumentary system, including its structure, functions, and clinical applications. It describes the layers of the skin, hair and nails, and discusses pigmentation. Conditions like infections, tumors, injuries, and disorders are explained. Careers like dermatology are also mentioned. Medical procedures for the skin like grafts, artificial skin, and transdermal medications are highlighted.
The document provides an overview of the structure and functions of the integumentary system. It describes the layers of the skin, including the epidermis and dermis. It outlines the principal cells of the epidermis and layers of the epidermis. It also discusses the structure and regions of the dermis, skin pigmentation, accessory structures like hair and glands, and the functions of the skin like protection and thermoregulation. Finally, it covers wound healing, scar formation, and age-related changes to the skin.
Training presentation for a company who has employed the parallel import strategy of importing their cosmetivs. Since they do not have the resources of the local agents, I have been commissioned to accummulate all information pertaining to their stocked products and supply a fully comprehensive training presentation.
The document discusses the structure and function of the integumentary system, specifically the skin. It describes the three main layers of skin - the epidermis, dermis and hypodermis. The epidermis contains keratinocytes, melanocytes, Langerhans cells and Merkel cells. It has several layers with different functions. The dermis contains collagen, elastic fibers, blood vessels and glands. It is made up of papillary and reticular layers. The hypodermis contains fat and connective tissue. Skin color is determined by melanin, hemoglobin and carotene. Hair, nails and glands are important accessory structures of the skin.
Skin is the largest organ or outer protective covering of body. It is composed of three layers: epidermis, dermis or subcutaneous tissues.
Skin is the body's defense covering, which protects against heat, light, injury and infection.
The skin is the largest organ of the body, with a total area of about 20 square feet. ... Skin has three layers: The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone. The dermis, beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands.
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
3. Structure of Skin
The integumentary systemis the largest body
organ and is composed of the skin, hair, nails,
and glands.
The skin has three layers
namely;
Epidermis
Dermis
Hypodermis
4. Epidermis
Epidermis is the outer layer of the skin, defined as a
stratified squamous epithelium, primarily comprising
keratinocytes in progressive stages of differentiation
Epidermis regenerates newcellsevery28days
The Epidermis is Avascular(has no blood
vessels)
Primary function is to act as a physical
and biological barrier to the external
environment.
5. Layers of the Epidermis
Layers of Epidermis ;
Stratum corneum – Superficial layer, the stratum corneum
is the outermost strata of the epidermis. It is mostly dead
cells, filled with a protein substance called keratin.
Stratum lucidum – Layer that is present only in the soles
and palms
Stratum granulosum – Alayers of flattened keratinocytes
producing keratin
6. Layers of the Epidermis
Layers of Epidermis ;
Stratum spinosum – Cells contain thick bundles of
intermediate filaments made of pre-keratin.
Stratum Basale - Stratum Basale lies deepest part of
the cell layer of the epidermis close to the dermis.
Stem cells in this layer are constantly dividing, and
millions of new cells are produced daily; hence the
alternate name Stratum germinativum.
8. Cells of Epidermis
Two Major types of epidermal cells:
Melanocytes and Keratinocytes
Melanocytes are found and contained in the deep, basal layer
( stratum germinativum) of the epidermis
Contains melanin, a pigment that gives color to the skin and
hair and protects the body from UV sunlight. Freckles and moles are
the result of the high concentration of melanin in one spot.
Sunlight and hormones stimulate the melanosome to increase
production
9. Cells of Epidermis
Two Major types of epidermal cells:
Melanocytes and Keratinocytes
Keratinocytes are synthesized from epidermal cells in the
basal layer
As they keratinize, they move to the surface, where they
flatten and die to form the outer layer of the skin (Stratum
Corneum)
Keratinocytes produce a fibrous protein, keratin, which is
vital to the skin’s protective barrier function.
10. Structure of the Epidermis
As new cells are produced, some
become epidermal cells, and others
maintain the population of stem cells
by continuing to divide. The daughter
cells destined to become epidermal
cells are pushed upward, away from
the source of nutrition, to become
part of the epidermal layers closer to
the skin surface. As they move away
from the dermis and become part of
the more superficial layers, the
stratum spinosum and then the
stratum granulosum, they become
flatter and increasingly keratinized.
How it works?
11. Dermis
Dermis is the connective tissue below the epidermis.
Unlike the epidermis, the dermis is very vascular.
It contains the lymphatics, nerves, nerve
endings, blood vessels, sebaceous and
sweat glands, elastic fibers, and hair
follicles.
The primary role of the dermis is to sustain
and support the epidermis.
12. Dermis
Divided into two layers: Upper thin Papillary layer
and a deeper, thicker Reticular layer
The papillary layer is folded into ridges which extend into the
upper epidermal layer. These exposed surface ridges form
congenital patterns called fingerprints and footprints.
The reticular layer is the deepest skin layer. It contains
irregular connective tissue, as well as blood vessels, sweet
and oil glands, and deep pressure receptors called lamellar
corpuscles.
13. Dermis
The dermis is abundantly supplied with blood vessels that
play a role in maintaining body temperature homeostasis.
14. Subcutaneous Tissue
The subcutaneous tissue or hypodermis lies deep
the dermis, it is often discussed with the skin
because it attaches the skin to underlying tissues
such as muscle and bone.
The subcutaneoustissue containsloose
connectivetissue andfat cellsthat provide
insulation.
The subcutaneoustissue isnot apart of the
skin.
15. Skin Color
Three pigments contribute to skin color: melanin,
carotene, and hemoglobin.
Melanin- brown- black , red-yellow pigment
Carotene- Yellow-orange pigments
Hemoglobin- Red color of oxygenated blood
16. Melanin
Melanin- is made in the skin and is the primary
pigment that determines the skin color.
The sunlight exposure stimulates melanocytes
to produce more melanin pigment, resulting in
tanning of the skin.
People who produce a lot of melanin tend to
have brown-toned skin, whereas people with
less melanin are light skinned
17. Melanin
As the melanocytes produce melanin, it accumulates
in their cytoplasm in membrane-bound granules called
melanosomes. These granules then move to the ends
of the melanocytes’ spidery arms, where they are
taken up by nearby keratinocytes. Inside the
keratinocytes, the melanin forms a pigment umbrella
over the superficial, or “sunny,” side of their nuclei and
shields their genetic material (DNA) from the
damaging effects of UV radiation in sunlight
18. Carotene
Carotene is an orange-yellow pigment plentiful
in carrots and other orange, deep yellow, or
leafy green vegetables.
The people who eat large amounts of
carotene-rich foods, the skin tends to take on a
yellow-orange cast,
19. Hemoglobin
Hemoglobin is the pigment in red blood cells.
In light-skinned people, the crimson color of
oxygen-rich hemoglobin in the bloody supply
flusher through the transparent cell layers
above and gives the skin a rosy glow.
21. Emotion and skin color
Emotion may also influence skin color
Redness or Erythema – reddened skin may indicate
embarrassment, fever, hypertension, inflammation, or allergy.
Jaundice or yellow cast – an abnormal yellow tone usually
signifies liver disorder.
Bruises- the black-and-blue marks of bruising reveal sites where
blood has escaped from the circulation and has clotted in the
tissue spaces.The clotted blood masses are called hematoma.
Blanching or Pallor- Under certain types of emotional stress.
23. Cutaneous Glands
Cutaneous Glands are all exocrine glands that
release their secretions to the skin surface via ducts.
Sebaceous glands secrete sebum, which is
emptied into the hair follicles.
Sebaceous glands are found all over the
body except palms of the hand and soles of the
feet.
Two major types of glands associated with the skin is
the Sebaceous Glands and Sweat Glands
24. Sebaceous Glands
Sebaceous glands also called oil glands
Sebaceous glands’product is called Sebum It is a
mixture of oily substance which act as a lubricant to
keep skin soft and moist and prevent hair from
becoming brittle. It also contains chemicals that kill
bacteria in the skin.
Sebaceous glands are more active when androgens
(male sex hormones) are produced.
25. Sebaceous Glands
---When sebaceous gland ducts are blocked by
sebum, acne appears on the skin surface. Acne is
an active infection of the sebaceous glands. If the
accumulated material oxidizes and dries, it
darkens, forming a blackhead. If the material
does not dry or darken, a whitehead forms. Acne
can be mild or extremely severe, leading to
permanent scarring.
26. Sweat Glands
Sweat Glands has two types namely Eccrine
and Apocrine.
Eccrine glands are far more numerous and are
found all over the body.
Eccrine glands produces- Sweat, , a clear
secretion that is primarily water plus some salts
,vitamin C, traces of metabolic wastes and lactic
acid.
Eccrine glands are important in body-heat
regulation.
27. Sweat Glands
Apocrine glands are largely confined to the
axillary (armpit) and genital areas of the body.
There is a secretion in the apocrine glands that contains fatty
acids and proteins, as well as all the substances present in
eccrine sweat. May have milky or yellowish color. The secretion
is odorless, but when bacteria that live on skin use its protein
and fats as a source of nutrients, it can take on a musky,
sometimes unpleasant odor.
28. Hair
Hair is a flexible epithelial structure. The part of the
hair enclosed in the hair follicle is called the root,
and the part projecting from the surface of the scalp
or skin is called the shaft.
A hair forms by division of the
well-nourished stratum Basale
epithelial cells in the matrix
(growth zone) of the hair bulb at
the deep end of the follicle.
29. Hair Follicle
Hair follicles are actually compound structures. The
inner epithelial root sheath is composed of epithelial
tissue and forms the hair
Arrector pili- connect each side
of the hair follicle to the dermal
tissue. When these muscles
contract the hair is pulled
upright, dimpling the skin surface
with “goose bumps.”
30. Nails
Nails are simply scale-like modifications of the epidermis
which have been heavily keratinized. The stratum
Basale (site of growth) extends below the nail bed.
Their lack of melanin makes them colorless.
Each nail has a free edge, a body
and a root (embedded in the
skin).The borders of the nail are
overlapped by folds of skin called
nail folds.
31. Nails
The stratum basale of the epidermis extends beneath the nail
as the nail bed. Its thickened proximal area, called the nail
matrix, is responsible for nail growth. As the matrix produces
nail cells, they become heavily keratinized and die. Thus, nails,
like hairs, are mostly nonliving material..
32. Review Questions
1.) What are the three concentric regions of a hair shaft, from the outside in? cuticle, cortex, medulla
2.) What is serbum? Oily secretion of the sebacceous glands
3.) How do secretions of apocrine glands differ from those of the eccrine sweat glands?
-Both are dilute salt solutions containg vitamins and wastes.Apocrine secretion also contains proteins and fatty acids
4.) When a factory worker caught his finger in a machine, the engine nail,plus the nail matrix and bed, was torn off. Will his
nail grow back? Why or Why not?
-No, the nail won't re-grow because the growth region is torn off.
5.) Why do no skin cancers develop from stratum corneum cells?
-Because stratum corneum cells are dead
6.) What change in aging skin accounts for wrinkles and cold intolerance in older adults?
-Loss of subcutaneous fat