The function of synovial fluid is to lubricate the joints and to act as a medium for nutrients to maintain the cartilage. The cells that maintain the cartilage have no blood, nerves or lymphatic ducts connected to them, so the synovial fluid is the only way they are supplied.
The synovial fluid is primarily filtered from blood fluids, with a large amount of hyaluronic acid added. This acid gives the synovial fluid a rather thick viscous consistency. Without it, the fluid has about the same consistency as water. It also contains about as much glucose as the blood. Indeed, it matches the chemical makeup of serum in many areas and contains mostly the same proteins in lower amounts, but it lacks most blood cells. It also lacks any coagulation proteins. It does contain some lymphocytes, or white blood cells, which fight pathogens.
The synovial fluid lubricates joints by introducing a slight separation between the joint's cartilage surfaces. The chemicals in synovial fluid cause it to stick to and coat synovial surfaces. With industrial lubricants such as motor oil, the moving parts always go in the same direction and so pull a wedge of fluid between them. Joints in animals move in many directions and so cannot use this mechanism.Learn More
Regulation of metabolic pathways is accomplished through the control of enzymatic activities, explains Collin College. The cell accomplishes this by either altering a pre-existing enzyme's activity or changing the available amount of a particular enzyme, according to College of Saint Benedict and Saint John's University.Full Answer >
As stated by WebMD, signs of an underactive thyroid, or hypothyroidism, include feeling tired, sluggish or weak, coarse and thinning hair, an inability to tolerate cold, memory problems, depression and difficulty concentrating. The most common cause of hypothyroidism in the United States is Hashimoto's thyroiditis, in which the immune system attacks the thyroid.Full Answer >
The thalamus is concerned with the motor control that people have over their bodies. It also helps to regulate a person's sleep and wake cycles. It receives signals related to vision, hearing, taste and other bodily sensations, and it sends these signals on the cerebral cortex. However, the thalamus doesn't process the sense of smell. In many ways, the thalamus serves as a relay center for the brain.Full Answer >
During the process of menstruation, progesterone responds to the activity of the ovarian follicles as they prepare to release an egg and causes the uterus to thicken its lining in preparation for a possible pregnancy. Progesterone levels increase during the last two weeks of the menstrual cycle and initiate protein secretion in the endometrium to support a fertilized egg once it is implanted, notes the National Women's Health Resource Center.Full Answer >