L5 Circ Resp and Buoyancy Flashcards
Explain the Bohr and Root effect
Bohr:
Root:
Agnathan Circulation
Heart - ventral aorta - afferent brach. art. - gills - efferent brachial art. - dorsal aorta - organs circulation.
Elasmobranch circulation
Heart - vent aort - aff. brach. art - gill ** - eff brach art. - dorsal aort. - organs
** cardiac artery supplies O2 rich blood back to heart
Teleost Circulation ** Review
From organs - caudal vein - Duct of Cuvier - heart - subbranchial art/afferent brach art?? - gill - efferent brachial art - Have R and L dorsal aorta …
Secondary circulation*** : supply capillary beds in epidermis of exposed scales (50% plasma which means maybe immuno function)
Compare heart in shark vs bony fish
Shark: sinus venosus (valve)- atrium (valve) - ventricle - conus arteriosus (contractile with valves) - ventral aorta
Bony fish: sinus venosus (w valve, muscular to fill atrium) - atrium (valve) - ventricle (conus arteriosus valve) - bulbus arteriosus (expands to maintain constant pressure through contraction) - ventral aorta
Brachiostegal Pump
Two cavities
Mouth opens and buccal cavity fills
Parabranchial cavity enlarges and fills, water over gills and still flowing in
Mouth closes and cavities contract, water over gills and out operculum
Teleost gill structure
Afferent artery - lacunae and central sinus - efferent artery
** pressure drop of 30-60% between aortas - allows sufficient time for gas exchange
Gas Bladders
Physoclistous
- all gas absorption/secretion must happen through
Physostomous
- has pneumatic duct for rapid absorption/secretion of gas from gas bladder
Gas secreted into gas bladder via gas gland. Blood pressure is at 0.2 atm while gas bladder pressure at 100 atm. Have rete mirable for countercurrent multiplier
- lactic acid secretion into blood lowers pH (O2 has lower binding affinity - Bohr and gases less soluble - Root) which increases gas efflux from the blood
