A microscope unit positioned in a culturing space for imaging cells or tissues also located therein. The microscope unit has a frame, an object holder provided on the frame and allowing the cells or tissues to be held substantially immobile during a culturing period, an imaging device arranged on the frame for the optical imaging of the cells or tissues held on the object holder and an image capturing device for capturing an image projected by the imaging device. A connection leading out of the culturing space provides electrical power to the microscope unit and is adapted to be connected to a control unit and, in turn, a processor, both located outside of the culturing space. The invention also relates to a method for monitoring cells or tissues located in the culturing space and transmitting the image thereof.