A measurement cell (3) for measuring at least one constituent of a liquid sample, in particular blood, includes a reception space (9) for receiving the sample includes a measurement system (8) having at least one sensor electrode (10) exposed within the reception space; a first heat supply equipment (12) extending over a first area (91); a second heat supply equipment (14) extending over a second area (93), the first and second heat supply equipment being arranged to heat the sample within the reception space (9), wherein the second area (93) is larger than the first area (91).