Stephen Hawking: 'There is no heaven; it's a fairy story'. In an exclusive interview with the Guardian, the cosmologist shares his thoughts on death, M-theory, human purpose and our chance existence. , science correspondent. Sunday 15 May 2011 17.00 EDT First published on Sunday 15 May 2011 17.00 EDT.
Both the growth of a tumor and the repair of a scrape on the knee are similar because they involve a mass amount of blood cells in a particular area. A growth of a tumor is a huge mass of cells that form together an cause it. And like the forming tumor, when you get a scrape on your knee blood cells are clumped together forming a large mass of blood also. They are different because there isn't an opening to a tumor allowing blood cells to flow out. When there is a scrape on your knee, there is an opening/cut, allowing blood cells to flow out properly.
Knee pain can come from injuries including sprains, swollen or torn ligaments (anterior cruciate ligament or ACL), meniscus or cartilage tears and runner's knee. Sports injuries tend to affect one knee at a time. Pain in both knees is more common with arthritis, osteoarthritis, gout or pseudogout, usually later in life. Conditions that cause knee pain. Tendonitis. This is an overuse injury causing swelling of the tendons, the bands of tissue that connect your bones and muscles. This is sometimes called 'jumper's knee' as it is common in sports involving jumping, such as basketball. Bone chips. Sometimes, a knee injury can break off fragments from the bone or cartilage. These pieces can get stuck in the joint, causing it to freeze up. You may also have pain and swelling. Housemaid's knee or bursitisis caused by kneeling for long periods of time or repetitive knee movements.