Describe the activities that take place in the stroma in bright sunlight and darkness.?

THYLAKOIDS the term used to describe the cholorophlasts internal membrane where it is organized into flattened membranous sacs. 

The thylakoids are arranged in orderly stacks called grana that contain energy-transducing machinery.

The space inside the thylakoid sac is called lumen and the space outside the thylakoid sac but still within the chloroplast is called stroma.