They re called granum singular and grana plural
Clouds form as a result of the condensation of water vapor in the atmosphere. They are made of tiny droplets of water. Clouds tend to form between 3pm and 6pm because this is when the region starts to loose or has completely lost the heat form the daily sun. Water vapor will condense once temperatures are low or are decreasing.
If you are going from a high gradient to a low gradient it’s passive transport. Think of a hill if you put a rock at the top of that hill it will go down no energy involved. Active transport is going up the hill you must use energy to push that rock up the hill because it’s from a low gradient to the top. Hope this helps
In this zone, the intensity of light rapidly dissipates as depth increases. Such a minuscule amount of light penetrates beyond a depth of 200 meters that photosynthesis is no longer possible. The aphotic, or “midnight,” zone exists in depths below 1,000 meters (3,280 feet).