Some photosynthetic organisms contain chloroplasts that lack photosystem ii, yet are able to survive. the best way to detect the lack of photosystem ii in these organisms would be to test for liberation of o2 in the light. to determine if they have thylakoids in the chloroplasts. to test for co2 fixation in the dark. to the action spectrum for photosynthesis.

the circled areas are referred to   as sunspots.   the sunspots are cooler than the   surrounding area.

sunspots are temporary phenomena on the photosphere of the sun that appear visibly as dark spots compared to surrounding regions. they correspond to concentrations of magnetic field flux that inhibit convection and result in reduced surface temperature compared to the surrounding photosphere.