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 by which plants use the energy of light to produce carbohydrates and molecular oxygen (O 2 ) from carbon dioxide (CO 2 ) and water: Virtually all ecosystems on Earth depend on photosynthesis as their source of energy, and all free oxygen on the planet, including that in the atmosphere, originates from photosynthesis. The overall reaction is the reverse of respiration, which releases energy by oxidizing carbohydrates to produce CO 2 and water.