The movement of materials into Bowman's capsule is opposed by two forces.
1) Capsule pressure (CP) produced by the walls of Bowman's capsule and fluid already
inside the capsule.
2) Colloid osmotic pressure (COP) results from the proteins in the blood. Because most proteins do not pass from the blood into the filtrate, the blood is more concentrated than the filtrate. Therefore water tends to move from the capsule back into the blood.
An increase in blood pressure or an increase in blood volume can lead to an increase in the amount of fluid entering Bowman's capsule (glomerular filtration rate) due to increased glomerular blood flow. This can be seen in conditions such as hypertension or congestive heart failure.
I believe youre asking what fluid makes the joints movement fluid... the answer is synovial fluid, made of mostly water. Its held between the bones by an overall structure called the joint capsule. There are smaller, more specific parts of the joint capsule, but I wont go into detail. Synovial fluid is not secreted by the joint capsule or the surrounding cartilage, however. Since the capsule is richly vascularized but poorly innervated, it just takes in water from the bloodstream whenever necessary to keep the capsule filled. It does not create its own synovial fluid.
A joint capsule is made up of tough fibrous connective tissue that surrounds a joint and is filled with synovial fluid. This fluid helps to lubricate the joint, reducing friction between the bones during movement.
The kidney.vasa recta
Synovial - the articulating bone ends are covered with articular cartilage, and enclosed within an articular capsule that is typically reinforced by ligaments externally. Internally the fibrous capsule is lined with a smooth synovial membrane that secretes synovial fluid.
A fluid-filled sac, such as a bursa or a synovial joint capsule, acts as a cushion to reduce friction between moving parts of the body. It helps to lubricate joints and facilitate smooth movement.
filtrate
Many structures within the kidneys rely on fluid pressure. The glomerus, Bowman's capsule, and tubules are all parts of the kidney that rely on fluid pressure to move the urine components along.
The outer layer of the joint capsule produces a fibrous membrane known as the synovial membrane. This membrane secretes synovial fluid, which helps to lubricate and nourish the joint, reducing friction and allowing smooth movement between the bones.
Many structures within the kidneys rely on fluid pressure. The glomerus, Bowman's capsule, and tubules are all parts of the kidney that rely on fluid pressure to move the urine components along.
Bowman's capsule
They increase the fluid exchange inside the joint capsule, helping synovial fluid lubricate the surfaces so they have less friction.