That's a good question. Since the test no longer encompasses plant biology, are we responsible for knowledge of photosynthesis? The logical answer would be no. Please let me know when you find out.
Edit: Ok, I think I've figured it out. You know how textbooks are divided into major sections such as Cellular Processes, Inheritance, Evolution, Plants, Animals, etc? I think the PCAT is following this same organization. Photosynthesis is more of a concern at the cellular level as opposed to the thorough study of plants. It is found under "cellular processes" as opposed to "plants" in textbooks. Based on this, I will study for photosynthesis until further information comes in.