Dehydration affects how plants' photosystems work. When chloroplasts or their parts are dehydrated, the flow of electrons between photosystems is blocked. Photosystem 1 is less affected by dehydration than photosystem 2. Dehydration makes both photosystems more heat-resistant. Photosystem 2 stops working when water is removed but can partially recover when rehydrated. The study found that dehydration doesn't change the amount of P700 capable of photooxidation. The dark reduction of photooxidized P700 in films shows two different phases, depending on how long the sample is illuminated. Overall, dehydration impacts how plants' photosystems function and their ability to withstand heat.