Causes of facet disease. Facet disease may arise when the cartilage in a facet joint is worn down as a result of aging, injury or wear and tear. This type of spinal damage can be attributed to arthritis, work, overuse or an injury sustained in an accident.acet disease occurs when a facet joint degenerates. While this can take place at any level of the spine, it most commonly affects the lumbar (lower spine) region. 1  Facet arthritis. 2  Facet joint syndrome. 3  Facet disease.
The raw materials of photosynthesis, water and carbon dioxide, enter the cells of the leaf, and the products of photosynthesis, sugar and oxygen, leave the leaf. Cross section of a leaf, showing the anatomical features important to the study of photosynthesis: stoma, guard cell, mesophyll cells, and vein.
Photosynthesis is the process used by plants, algae and certain bacteria to harness energy from sunlight into chemical energy. There are two types of photosynthetic processes: oxygenic photosynthesis and anoxygenic photosynthesis. Oxygenic photosynthesis is the most common and is seen in plants, algae and cyanobacteria. During oxygenic photosynthesis, light energy transfers electrons from water (H 2 O) to carbon dioxide (CO 2), which produces carbohydrates. In this transfer, the CO 2 is reduced, or receives electrons, and the water becomes oxidized, or loses electrons. Ultimately, oxygen is produced along with carbohydrates. Oxygenic photosynthesis functions as a counterbalance to respiration; it takes in the carbon dioxide produced by all breathing organisms and reintroduces oxygen into the atmosphere.