Chlorophyll is found in and around the photosystems embedded in the thylakoid membrane of the chloroplasts.
The chloroplasts are organelles found in eukaryotic algae. The chloroplasts in eukaryotic celss are contained in the cytoplasm together with other organelles.
Since the chlorophyll is insided the chloroplast which is inside the cytoplasm, it is safe to say that the chlorophyll of the green algae is spread throughout the cytoplasm of its cells.
