3.1.1 Flashcards
(26 cards)
metabolic rate summary
energy expelled/ time
basal = at rest
estimated by O2 consumption/ CO2/ heat production
need for specialised exchange surfaces
low SAV, high metabolic demand, diffusion distance too large between surface and centre - supply O2 and remove CO2/ waste
no need for specialised exchange surfaces as…
high SAV, low metabolic demand, short diffusion distance so simple diffusion is enough
exchange surface features
good blood supply (maintain gradient)
short diffusion distance
high SA
Ventilation system
moist for gasses to dissolve
inspiration
diaphragm contracts & flattens
ext. intercostal contract
ribs up and out
thorax V↑ P↓
air drawn in
expiration (+forced)
diaphragm relax & dome
both intercostal relax
ribs down and in
thorax V↓ P↑
air out
forced is more force and int. intercostal contracts
how spirometry works
clip nose for closed system
inhaling & exhaling uses O2 and produces CO2
CO2 absorbed by soda lime
as volume in spirometer rises and falls, a trace is drawn
vital capacity
max volume in 1 breath
tidal volume
volume of 1 breath at rest
breathing rate
number of breaths/ minute
inspiratory & expiratory reserve system
extra air storage for exercise
total lung capacity
vital capacity + residual volume (air always in lungs)
trachea summary
ciliated epithelium, elastin + smooth, b.vessels, mucous glands and C-shaped cartilage
insect air flow
spiracle to trachea to tracheole to muscle/ respiring cells
insect trachea material
chitin
why do insects need specialised system
exoskeleton prevents direct exchange
too large for simple alone
insect tracheal fluid mechanism
anaerobic resp so lactic so water/ fluid moves from tracheole into cells
more air for diffusion in tracheole
fluid in gaseous exchange
alveoli surfactant
tracheolar fluid in insects
allow gas to dissolve and faster diffusion
ventilation in fish
buccal cavity
over gills
opecular cavity
out operculum
caused by change in pressure by opening or closing
exchange flow in fish
countercurrent, opposite to maintain concentration grad along entire lamellae, very efficient
opposite of countercurrent
concurrent, only reaches equilibrium
fish gill anatomy
gill raker to arch to filament to lamellae
problem with aquatic environment and gas exchange
diffusion is slower in water
lower oxygen concentration
insects mechanical ventilation
e.g. in large insects or in flight
spiracles close to target
abdomen contracts
enlarged trachea and air sacs used as air resevoirs
