Biology Day 8 Flashcards
Protection from pathogens and particultes
in lungs
Thermoregulation
significant amount of heat is lost to expired air
nose hairs and mucous
prevent pahtogens from reachign lungs
goblet cells
secrete mucus lining in the respiratory tract
cilia propel
mucus and pathogents
macrophages in alveoli
phagoctose
respiratoy system
pharynx, larynx, trachea, primary bronchi, bronchi, bronchioles, alveoli
exchange surface
bronchioles/alveoli
associated muscles, bones, of the thoraci cavity
diaphram, abdomianal muscles, intercostals, rib cae
alveoli
air-filled sacs surrounded by cappliaries, thin walled with huge surface area, cated with surfactant(reduces tention),
make up to 95% of alveolar walls and is the site of gas exchange
type I alveolar cells
secrete surfactant
type II alveolar cells
inspiration is caused
by Contraction of the diaphram
the lungs are surrounded by
two plueral sacs
diaphram is connected
to the outer pleural sac
expansion of the lungs
LOWERS the presssure inside them
the diaphram is innervated by
the somatic nervous system
inspriation cna be
voluntary or involuntary
expiration
passive elastic recoil of the lungs (resiliency)
forced expiration involves
contraction of the abdominal and intercostal muscles.. noramlly experiation is involuntary
Human skin
prevent loss of water, impermeable to water
Skin, thermoregulation
heat retention, heat removal, physical protection, dermal layers,
heat retention
hairs help with heat retention, errect when cold, hypodermis contains an insulating layer of adiipose tissue to prevent heat loss, vasocontriciton of the suface capillaries in the dermis minimizes heat loss
heat removal
sweat glands in the dermis release sweat(water and salt), evaporation removes heat, vasodialiation of the suface capliarries in the dermis increases heat loss thorugh the skin,
Physical protection,
skin protects form pathogens, fingernals and toe nales, made of kertin, protect ends, callus build up protects areas more prone to abrasion
dermal layers
Epidermis, composed of stratified squamous,
Dermis- composed of loose connective tissue, contains blood vessels, never ending and exocrine glands
Hypodermis- contains adipose tissue for insulation
