title bar for isopod file   Physiological ecology   black dot
Gas exchange    Gas exchange is considered here, while topics of
OSMOTIC REGULATION and BEHAVIOUR are dealt with in their own
sections. Research study 1  photo/drawing composite showing
location of gas-exchanging pleopods in an isopod Idotea
wosnesenskiiThe 5 pairs of pleopods on the ventral surface of
the abdomen in marine isopods function both for locomotion
(swimming) and gas exchange.  A pair of large opercula (modified
uropods) protects the pleopods and together these units form a
branchial chamber.  The pleopods beat cyclically to ventilate
the chamber. The question arises as to whether all pleopods
function in gas exchange, or is there a division of labour
between them?  Put in another way, have the swimming pleopods
retained or lost their gas-exchange capability?  This is
examined in Idotea wosnesenskii at the Oregon Institue of Marine
Biology by removing sets of pleopods (1-3 and 4-5) in different
animals, and measuring before-and-after v