Two reasons: Aspirin has a direct potentially erosive effect on the stomach lining causing the lining to become inflamed , especially on an empty stomach and thus can contribute to creation or perpetuation of a breach in the stomach lining (an ulcer).
Photosynthesis is a process used by plants in which energy from sunlight is used to convert carbon dioxide and water into molecules needed for growth. These molecules include sugars, enzymes and chlorophyll.
Green plants absorb light energy using chlorophyll in their leaves. They use it to react carbon dioxide with water to make a sugar called glucose. The glucose is used in respiration, or converted into starch and stored. Oxygen is produced as a by-product. This process is called photosynthesis.