Changes in <i>C. velia</i> C, N, C∶N and carotenoids during a sinusoidal light∶dark cycle.

<p>Changes in C (pg C cell⁻¹, panel A), the ratio of C∶N (mol∶mol, panel B), N quotas(pg N cell⁻¹, panel C) and the major carotenoids relative to chl <i>a</i> (presented as ratio per chl <i>a</i>, panel D) are shown. Error bars are calculated as standard deviations of n≥3 replicated. Average values (plus error bars) measured for LL (▪) and HL (□) grown <i>C. velia</i> are included for comparison. The dashed line shows the light intensity during the light part of the cycle, with a midday peak of 500 µmol photons m⁻² s⁻¹.