Lecture 8 - Part 1 Flashcards
the largest organ system, that protects the body from damage, comprising the skin and its appendages
integumentary system
attachment site for sensory receptor to detect pain, sensation, pressure, and temperature
integumentary system
What are the functions of the integumentary system?
waterproof
cushion
protect the deeper tissues
excrete wastes
regulate temperature
has soft, delicate, and mucus-secreting gland epidermis, which secretes the – of the cell
Molluscs; calcium carbonate
Cephalopod molluscs (squids and octopuses) have developed a more complex integument that is a layer of reflecting cells called –
iridocytes
has the most complex – protection and support
Arthropods
The arthropod integument consists of a single-layered epidermis (more precisely called hypodermis), which secretes a complex cuticle of two zones which are the –
epicuticle and procuticle
outer, thin, nonchitinous cuticle
epicuticle
inner, thick, chitinous cuticle
procuticle
a crustacean’s (crabs and lobsters) cuticle is hardened by a process called –
calcification
an insect’s cuticle is hardened by a process called –
sclerotization
deposition of calcium carbonate in the outer layers of the procuticle.
calcification
cross-linking of procuticle proteins forming a
highly resistant and insoluble protein
sclerotization
a highly resistant and insoluble protein formed in sclerotization
sclerotin
arthropods undergo molting. What do you call the sloughed-off exoskeleton?
exuviae
thin, outer, stratified epithelial layer derived from ectoderm
epidermis
inner, thick layer, derived from mesoderm
dermis
the epidermis is derived from
ectoderm
the dermis is derived from
mesoderm
known as the true skin
dermis
the technical term for our skin
cutaneous membrane
the inner lining of some organs and body cavities such as the respiratory organs
mucus membrane
the inner lining of some organs and body cavities such as the respiratory organs
mucus membrane
Functions of Skin
- Protects from injuries
- Acts as barrier and regulates what enters/leaves body.
- Regulates body temperature.
- Synthesizes, stores vitamins.
- Sensory functions
Structures of the Skin: EPIDERMIS
- Upper layer of the skin
- Thin
- Avascular
- Stratified squamous
stratum basal is also known as
stratum germinavatum
a sublayer of the epidermis in constant mitosis
stratum germinavatum
- Basal layer
- Dividing cells
- Good nutrient supply
- Regeneration of skin
stratum germinavatum
- Living cells
- Dividing
- 8-10 cells thick
- Polygonal in
appearance
stratum spinosum
- Poor nutrient supply
- Flatten layer of cells
- 3-5 cells thick
- No cell division
- keratinization
stratum granulosum
- Found only in very thick skin
- Translucent
- Highly keratinized
- Dead cells
stratum lucidum
- 25-30 cells thick
- Cornified cells
- Sloughed off
- Outermost layer
Stratum Corneum
Structure of the dermis
Irregular dense connective tissue
collagenous fibers
the dermis is composed of
- Sweat gland
- Sebaceous gland
- Arrector pili muscle
- Blood vessels
The layer of the dermis is a thin superficial layer of areolar tissue and heavily vascularized
papillary
The layer of the dermis is about 80% of the dermis, a typical dense irregular connective tissue, and contains bundles of interlacing collagen fibers that run parallel to the skin surface.
reticular
Consists of connective tissues (areolar & adipose).
Anchors skin to the underlying muscles
hypodermis (subcutaneous)
two types of skin appendages
Dermal derivatives and Epidermal derivatives
A dermal derivative that is also known as a dermal bone
ostracoderms
types of dermal derivatives
- dermal bone (ostracoderms)
- placoid scale (chondrichthyes)
- ganoid
- leptoid
- ctenoid scale
- osteoderms
A dermal derivative that is derived from embryonic nervous system
chromatophores
A type of chromatophore responsible for the brown to black pigments
melanophores
A type of chromatophore responsible for the yellow pigment
lipophores and xanthophores
A type of chromatophore responsible for the red pigment
erythrophores
A type of chromatophore responsible for the white pigment
guanophores
