Table 4.

Predicted excitation energy flow in S. elongatus acclimated to low and high light. ${\Phi }_{{\text{CO}}_2}$: quantum yield of net carbon fixation, ${\Phi }_{{\text{O}}_2}$: quantum yield of net oxygen evolution. Abbreviations: ET: energy transfer, PSII: photosystem II, PSI: photosystem I, CEF: cyclic electron flow, CR: charge recombination.

	Fraction of absorbed quanta									State Transition
	ET loss	PSII	PSI	CEF	PSII CR	PSI/PSII	D1 repair cost1	${\Phi }_{{\text{CO}}_{\text{2}}}$2	${\Phi }_{{\text{O}}_2}$2	PSI:PSII3	Y(II)4
High light	0.31	0.09	0.60	0.54	0.04	6.7	3.2×10−10	0.009	0.010	2.1	2.1
Low light	0.29	0.17	0.54	0.36	0.03	3.2	0.6×10−10	0.028	0.031

¹μmol ATP cell⁻¹ s⁻¹

²μmol × μmol⁻¹ photon

³(High light PSI/PSII)x(Low light PSI/PSII)⁻¹

⁴(Low light Y(II))x(High light Y(II))⁻¹