Infrapatellar bursitis occurs when one or both of the bursa sacs inside the knee become irritated and inflamed resulting in swelling and knee pain. A bursa is a sac of synovial fluid, rich in protein and collagen.
In biology, motility is the ability of organisms and fluid to move or get around. A microbiologist might test and compare the motility of various single-celled organisms. An easy way to remember that motility means the ability to move without help is the mot- at the root of the word. It's the same root that's found in motor, which is, of course, the engine that drives a car. If you've got good motility then your motor is working.
What Is Normal Sperm Motility? When sperm motility in a single ejaculate is 50% or more, this is seen to be normal. Even a lower motility, between 25% and 50%, may not lead to issues. However, when the motility is consistently under 25%, the risks of fertility problems are much greater.