This is called a monohybrid experiment. A test cross is performed between two plants that breed true for one trait, and the resulting trait for each offspring plant is determined The first, true-breeding generation, is called the parent, P generation.
Lumbar Degenerative Disc Disease Video. The natural history of lumbar degenerative disc disease is relatively benign. The pain tends to be intermittent, and although at times the pain may seem to be getting worse, the painful symptoms are generally not progressive. While the disc degeneration will progress, the low back pain and other symptoms do not tend to get worse with the progression of the degeneration.
Degenerative disc disease is a disease of aging, an age related disease. Over the years and decades, the repeated daily stresses on the spine and occasional minor, unnoticed injuries, as well as major ones, begin to take their toll.For most people the gradual degeneration of the discs is not a problem.However, in some cases it eventually causes severe, chronic and debilitating discogenic pain. Back specialists refer to pain caused by a damaged intervertebral disc as discogenic pain.s the human body ages, the intervertebral discs degenerate (break down), which leads to degenerative disc disease in some individuals. The changes that occur, due to aging, include: 1  Loss of fluid-the intervertebral discs of a healthy young adult consist mainly of fluid, up to 90%.