The term arthritis is used to describe numerous rheumatic diseases and conditions that affect joints. Some forms of arthritis, such as rheumatoid arthritis and lupus, can affect multiple organs and cause widespread symptoms.he term arthritis is used to describe numerous rheumatic diseases and conditions that affect joints. Some forms of arthritis, such as rheumatoid arthritis and lupus, can affect multiple organs and cause widespread symptoms.
The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The kidneys filter the blood to remove wastes and produce urine. The ureters, urinary bladder, and urethra together form the urinary tract, which acts as a plumbing system to drain urine from the kidneys, store it, and then release it during urination.
The ureter is the structure through which urine is conveyed from the kidney to the urinary bladder. To learn more about the structure of the kidney, see our simple (labelled) diagram of a kidney nephron.idney nephron: Kidney nephrons are the functional units of the kidneys. That this, it is the kidney nephrons that actually perform the kidney's main functions. There are approx. a million nephrons within each kidney. To find out more about these, visit the page about Kidney Nephrons.