Figure 1.

Comparison of net photosynthetic rate (●, ○), CO₂ uptake (▾, ▿), and HCO₃⁻ uptake (▪, □) for Symbiodinium sp. freshly isolated from the giant clam T. gigas (black symbols) and a 2-d-old culture (white symbols) with differing C_i concentrations. Assays were conducted in 25 mm BTP (pH 8.0), 428 mm NaCl, and 50 μm AZA at 28^OC with a photon flux density of 500 μE m⁻² s⁻¹. Data were collected using the mass spectrometry disequilibrium technique described in “Materials and Methods.”