As they move upward, the
BIO-13 Anatomy and Physiology - Made up of living cells. older cells become
flattened and their
Chapter 4 undergo organelles disintegrate.
Integumentary System Rapid cell division
Producing new cells that
push older cells to the
Structure: surface of the skin.
➢ Outer covering of the body. begin making keratin – tough, fibrous protein
➢ Skin with all its derivatives.
keratin – producing cells die and form a tough,
Functions: flexible, waterproof covering on the surface of the
skin.
➢ Covering and protection from mechanical
injury and entrance of foreign materials or --- this outer layer of dead cells is shed or washed
bodies. away at a surprising rate – once every four to five
➢ Secretion weeks. ---
➢ Excretion
➢ Sensation
➢ Respiration --- the epidermis also contains melanocytes
➢ Absorption (melanin – dark brown pigment) ---
➢ Regulation of body temperature
Warm-Blooded Animals
Although most people have roughly the same
- Regulated body temperature because oof number of melanocytes in their skin, differences
their heat-conserving body. in skin color are cause by the different amount of
o Body temperature stays the same melanin in the melanocytes produce and these
when its cold or hot outside. cells are distributed.
Cold-Blooded Animals
- Body temperature closely follows that of Epidermal Derivatives:
their environment.
o Body temperature depends on Ex. hair, nails, scutes, claws, horny scales,
whether its cold or hot outside. feathers, spines
Skin Other epidermal derivatives:
➢ Single largest organ of the body Ex. bills, beaks, horns, hoofs, enamel of the teeth,
➢ Protection (most important function) glands
➢ Contains sensory receptors – gateway Dermis (true skin)
through which sensations (pressure, heat,
cold and pain) are transmitted to the ➢ Inner
nervous system. ➢ Thicker layer
➢ Made up of mostly connective tissue
Vertebrate Integument fibers, smooth muscles, blood vessels and
Epidermis sensory nerve endings and tactile
corpuscles (specialized nerve endings that
➢ Outer respond to tactile, thermal and pain
➢ Thinner stimuli)
➢ Stratified layer of the skin ➢ Mesodermal in origin
➢ Consist primarily of cells
➢ Ectodermal in origin Dermal Derivatives
Outer Epidermis Ex. scales, bony plates, dentine, antlers
- Comes in contact with environment Subcutaneous Connective Tissue
- Made up of dead cells - Separates the skin from the underlying
--- There are no blood vessels in the epidermis --- muscles.
Inner Epidermis Other structures present in the skin
, 1. Chromatophores and Pigments Grow at an average rate of 3 mm per month
o Chromatophores – specialized (fingernails growing more rapidly than toenails –
connective tissue cells which about four times as fast)
contain pigments. e.g. frog
Nail root – rapidly dividing cells
o Melanophores – connective tissue
cells which contain black or brown Vertebrates
pigments (melanin) e.g. fishes,
amphibians and reptiles. Amphibians
2. Glands ➢ Thin
Types of Gland according to structure: ➢ Moist
o Unicellular Glands – one-celled ➢ Naked
glands e.g. lingual glands
o Multicellular Glands – many-celled Reptiles
glands e.g. mucous glands
➢ Thicker epidermis
Types of Gland according to the Type of
➢ Exoskeletal structures (scales, scutes and
Secretion:
plates) for protection and preservation of
o Serous Gland – watery, thin film of
body fluids
secretion
o Mucous Gland – slippery secretion Birds
due to mucin.
o Oil Gland (Sebaceous/Sebiferous ➢ Thin
Gland) – oily, thick secretion ➢ Loose
➢ Covered with exoskeletal structures
--- the basic structure of human hair and nails is (feathers, scales, claws and beak or bill)
keratin. --- for body covering, insulation, protection
and for flight.
Hair
Man
➢ Covers almost every exposed surface of
the body. Epidermis
➢ Protects the scalps of the head from UV
light from the sun and provides insulation • Stratum Corneum – non-living layer (sole
from the cold. and palm)
➢ Prevents dirt and other particles from • Stratum Lucidum – clear layer
entering the body (nostrils, external ear • Stratum Granulosum – granular layer
canals, and around eyes (eyelashes). • Stratum Spinosum – several layers of
thick, with cells having dark nuclei and
--- hair is produced by cells at the base of spiny projections
structures (hair follicles) --- • Stratum Basale – living or growing layer
--- rapid cell growth at the base of the hair follicle Dermis
causes the hair to grow longer ---
• Thick and strong but is not divided into
--- hair follicles are in close contact with
layers
sebaceous glands ---
• With glands present
--- its oily secretions help maintain the condition of
Oil gland
each individual hair ---
• Found all over the surface of the body and
-- the basic structure of hair and nails is keratin –
opens into hair follicles except palm and
Nail sole
➢ Protects the tips of the fingers and toes. Sweat gland
--- during cell division, the cells of the nail root fill • Found all over the surface of the body and
with keratin and produce a tough, plate-like nail opens into pores of the skin
that covers and protects the tips of the fingers
Mammary gland
and toes ---
• Secretes milk
BIO-13 Anatomy and Physiology - Made up of living cells. older cells become
flattened and their
Chapter 4 undergo organelles disintegrate.
Integumentary System Rapid cell division
Producing new cells that
push older cells to the
Structure: surface of the skin.
➢ Outer covering of the body. begin making keratin – tough, fibrous protein
➢ Skin with all its derivatives.
keratin – producing cells die and form a tough,
Functions: flexible, waterproof covering on the surface of the
skin.
➢ Covering and protection from mechanical
injury and entrance of foreign materials or --- this outer layer of dead cells is shed or washed
bodies. away at a surprising rate – once every four to five
➢ Secretion weeks. ---
➢ Excretion
➢ Sensation
➢ Respiration --- the epidermis also contains melanocytes
➢ Absorption (melanin – dark brown pigment) ---
➢ Regulation of body temperature
Warm-Blooded Animals
Although most people have roughly the same
- Regulated body temperature because oof number of melanocytes in their skin, differences
their heat-conserving body. in skin color are cause by the different amount of
o Body temperature stays the same melanin in the melanocytes produce and these
when its cold or hot outside. cells are distributed.
Cold-Blooded Animals
- Body temperature closely follows that of Epidermal Derivatives:
their environment.
o Body temperature depends on Ex. hair, nails, scutes, claws, horny scales,
whether its cold or hot outside. feathers, spines
Skin Other epidermal derivatives:
➢ Single largest organ of the body Ex. bills, beaks, horns, hoofs, enamel of the teeth,
➢ Protection (most important function) glands
➢ Contains sensory receptors – gateway Dermis (true skin)
through which sensations (pressure, heat,
cold and pain) are transmitted to the ➢ Inner
nervous system. ➢ Thicker layer
➢ Made up of mostly connective tissue
Vertebrate Integument fibers, smooth muscles, blood vessels and
Epidermis sensory nerve endings and tactile
corpuscles (specialized nerve endings that
➢ Outer respond to tactile, thermal and pain
➢ Thinner stimuli)
➢ Stratified layer of the skin ➢ Mesodermal in origin
➢ Consist primarily of cells
➢ Ectodermal in origin Dermal Derivatives
Outer Epidermis Ex. scales, bony plates, dentine, antlers
- Comes in contact with environment Subcutaneous Connective Tissue
- Made up of dead cells - Separates the skin from the underlying
--- There are no blood vessels in the epidermis --- muscles.
Inner Epidermis Other structures present in the skin
, 1. Chromatophores and Pigments Grow at an average rate of 3 mm per month
o Chromatophores – specialized (fingernails growing more rapidly than toenails –
connective tissue cells which about four times as fast)
contain pigments. e.g. frog
Nail root – rapidly dividing cells
o Melanophores – connective tissue
cells which contain black or brown Vertebrates
pigments (melanin) e.g. fishes,
amphibians and reptiles. Amphibians
2. Glands ➢ Thin
Types of Gland according to structure: ➢ Moist
o Unicellular Glands – one-celled ➢ Naked
glands e.g. lingual glands
o Multicellular Glands – many-celled Reptiles
glands e.g. mucous glands
➢ Thicker epidermis
Types of Gland according to the Type of
➢ Exoskeletal structures (scales, scutes and
Secretion:
plates) for protection and preservation of
o Serous Gland – watery, thin film of
body fluids
secretion
o Mucous Gland – slippery secretion Birds
due to mucin.
o Oil Gland (Sebaceous/Sebiferous ➢ Thin
Gland) – oily, thick secretion ➢ Loose
➢ Covered with exoskeletal structures
--- the basic structure of human hair and nails is (feathers, scales, claws and beak or bill)
keratin. --- for body covering, insulation, protection
and for flight.
Hair
Man
➢ Covers almost every exposed surface of
the body. Epidermis
➢ Protects the scalps of the head from UV
light from the sun and provides insulation • Stratum Corneum – non-living layer (sole
from the cold. and palm)
➢ Prevents dirt and other particles from • Stratum Lucidum – clear layer
entering the body (nostrils, external ear • Stratum Granulosum – granular layer
canals, and around eyes (eyelashes). • Stratum Spinosum – several layers of
thick, with cells having dark nuclei and
--- hair is produced by cells at the base of spiny projections
structures (hair follicles) --- • Stratum Basale – living or growing layer
--- rapid cell growth at the base of the hair follicle Dermis
causes the hair to grow longer ---
• Thick and strong but is not divided into
--- hair follicles are in close contact with
layers
sebaceous glands ---
• With glands present
--- its oily secretions help maintain the condition of
Oil gland
each individual hair ---
• Found all over the surface of the body and
-- the basic structure of hair and nails is keratin –
opens into hair follicles except palm and
Nail sole
➢ Protects the tips of the fingers and toes. Sweat gland
--- during cell division, the cells of the nail root fill • Found all over the surface of the body and
with keratin and produce a tough, plate-like nail opens into pores of the skin
that covers and protects the tips of the fingers
Mammary gland
and toes ---
• Secretes milk
