Page 84 - The Toxicology of Fishes

64 The Toxicology of Fishes

Blood flow

Tissues

Water flow Diffusion
C O 2

Water flow Gill filaments Water flow Arterial blood Anatomic and physiological model for oxygen uptake at fish gills. (A) Section through the head of a generalized teleost showing four pairs of gill

Gill arch Gill lamellae Afferent artery (from ventral aorta) Convection MO 2 = Q C (C aO 2 – C vO 2) arches; arrows show the direction of water flow through the buccal and opercular cavities. (B) Part of a gill arch showing two gill filaments with rows of lamellae on the ventral and dorsal surface. (Adapted from Wedemeyer, G.A. et al., Environmental Stress and Fish Diseases, TFH Publications, Neptune City, NJ, 1976.) (C) Transverse section of a gi

Cartilaginous rod Efferent artery (to dorsal aorta) Circulation

B Q c = 30 mL kg –1 min –1 Venous blood
Opercular cavity MO 2 = KA∆PO 2 h

Gill h = 6µ A = 3 cm 2 g –1 Diffusion

Buccal cavity Water –1 O 2 –1 V VOL = 300 mL kg min Convection V vol = F r V sr

A D
FIGURE 3.3