INTEGUMENTARY SYSTEM
INTEGUMENTARY SYSTEM FUNCTIONS
1. Covering and protection
2. Secretion (cutaneous gland)
3. Excretion of metabolic wastes (cutaneous gland)
4. Sensation (presence of nerve endings and tacticle)
5. Respiration – in frog
6. Absorption – in frog
7. Regulation of body temperature
HOMOIOTHERMOUS ANIMALS- warm blooded animals or those with regulated body temperature because of their heat-conserving body.
POIKILOTHERMOUS ANIMALS - cold blooded animals whose body temperature closely follows that of their environment.
INVERTEBRATE INTEGUMENTS Protozoa- delicate cell membrane (Amoeba) Coelenterata- epidermis, single layer of cells (e.g. corals and Hydra) Annelida- epidermis contains non-cellular cuticle (e.g. earthworm) Platyhelminthes- epidermis contain contains resistant cuticle (e.g. liver fluke and tape worm.) Arthropoda- chitin (e.g. shrimp, crabs, lobster and insects) Mollusca- shell (clams, mussels and oysters)
VERTEBRATE INTEGUMENTS
I. EPIDERMIS - outer, thinner but stratified layer of the skin
- Ectodermal in origin
- epidermal derivatives – hairs, nails, claws, scutes, hoofs, beaks and bills, horny scales, feathers, spines, enamels of the teeth, gland, horns.
II. DERMIS - inner, thicker layer of the skin.
Made up of mostly connective tissue fibers, smooth muscles, blood vessels and nerve ending
Mesodermal in origin.
Dermal derivatives of the skin- scale of fishes, antlers, dentine, and bony plates.
Subcutaneous connective tissues- connective tissue that separates the skin from the underlying muscles
Chromatophores- specialized connective tissue cells which contain pigments.
Types of Chromatophores
1. Melanophores- black or brown pigment (melamine)
2. Lipophores- red or yellow pigment (erythrocin and xanthin)
3. Quanophores- colorless, white crystalline materials (guanine) ex. Fishes
4. Photophores- make animal luminous. Ex. Deep sea shark
Human skin
I. Epidermis- four layers
1. Stratum corneum- the non-living
1. Covering and protection
2. Secretion (cutaneous gland)
3. Excretion of metabolic wastes (cutaneous gland)
4. Sensation (presence of nerve endings and tacticle)
5. Respiration – in frog
6. Absorption – in frog
7. Regulation of body temperature
HOMOIOTHERMOUS ANIMALS- warm blooded animals or those with regulated body temperature because of their heat-conserving body.
POIKILOTHERMOUS ANIMALS - cold blooded animals whose body temperature closely follows that of their environment.
INVERTEBRATE INTEGUMENTS Protozoa- delicate cell membrane (Amoeba) Coelenterata- epidermis, single layer of cells (e.g. corals and Hydra) Annelida- epidermis contains non-cellular cuticle (e.g. earthworm) Platyhelminthes- epidermis contain contains resistant cuticle (e.g. liver fluke and tape worm.) Arthropoda- chitin (e.g. shrimp, crabs, lobster and insects) Mollusca- shell (clams, mussels and oysters)
VERTEBRATE INTEGUMENTS
I. EPIDERMIS - outer, thinner but stratified layer of the skin
- Ectodermal in origin
- epidermal derivatives – hairs, nails, claws, scutes, hoofs, beaks and bills, horny scales, feathers, spines, enamels of the teeth, gland, horns.
II. DERMIS - inner, thicker layer of the skin.
Made up of mostly connective tissue fibers, smooth muscles, blood vessels and nerve ending
Mesodermal in origin.
Dermal derivatives of the skin- scale of fishes, antlers, dentine, and bony plates.
Subcutaneous connective tissues- connective tissue that separates the skin from the underlying muscles
Chromatophores- specialized connective tissue cells which contain pigments.
Types of Chromatophores
1. Melanophores- black or brown pigment (melamine)
2. Lipophores- red or yellow pigment (erythrocin and xanthin)
3. Quanophores- colorless, white crystalline materials (guanine) ex. Fishes
4. Photophores- make animal luminous. Ex. Deep sea shark
Human skin
I. Epidermis- four layers
1. Stratum corneum- the non-living