Integument Flashcards
functions of integument
protection
sensory
secretion
production
storage
thermoregulation
communication
how does the integument provide protection?
external barrier protects underlying structure- physical trauma and invading organisms
how does the integument provide sensory?
sensory nerve endings in surface of skin, monitor external environment
how does the integument provide secretion?
glands present in skin, produces secretions on surface
how does the integument provide production?
vitamin d synthesised in skin
how does the integument provide storage?
fat stored in hypodermis, provides energy and insulation
how does the integument provide thermoregulation?
mechanisms present to increase and decrease heat loss
how does the integument provide communication?
scents/pheromones produced, physical communication
what are the 3 layers of skin?
epidermis
dermis
hypodermis
define epidermis
superficial layer
stratified squamous epithelium
renewed by stem cells
define dermis
underlying layer
dense irregular connective tissue
define hypodermis
lies beneath the skin
areolar/adipose tissue
name of epidermis cells
keratinocytes
melanocytes
Merkel
Langerhans
function of keratinocytes
produces keratin, waterproof protein provides skin with resilience and strength
70-80% of skin cells, produced by ribosomes and packed by Golgi body
function of melanocytes
produces a melanin pigment
function of Merkel Cells
close to nerve endings, receive touch sensation
function of Langerhans Cells
involved in allergic and cell immune related responses
Base to Top
stratum Basale (base layer)
stratum spinosum (spiny layer)
stratum granulosum (granular middle layer)
stratum lucidum (clear layer)
stratum corneum (‘horny’ outer layer)
what does the dermis contain?
hair follicles
nerve endings
glands
smooth muscle
blood vessels
lymphatics
fibroblasts, adioplasts and macrophages
what are the 2 layers of the dermis?
papillary layer
reticular layer
define papillary layer
helps cement epidemris and dermis together, blood vessels, pain, temperature and touch receptors present- areolar tissuede
define reticular layer
provides strength and structure to skin, elastin and fibril microfibrils- stretch/glide/recoil
what is the hypodermis composed of?
blood and lymphatic vessles/nerves
special touch receptors: pacinian corpuscle and meissner corpuscle
