1 A blood clot that forms inside one of your veins or arteries is called a thrombus. A thrombus may also form in your heart.  A thrombus that breaks loose and travels from one location in the body to another is called an embolus.
The kidneys. The kidneys do vital work in the body filtering blood removing waste into urine, and balancing electrolyte levels. Our blood in our bodies passes through the kidneys several times a day. The kidneys are located at the back of the abdomen. Each kidney is about the size of a fist - 10-12.5cm long.
The kidneys are paired organs located toward the back of your body, partially protected by your lower ribs. Your left kidney is slightly higher than your right. Pain from the kidneys tends to occur in the flanks or in the lower back just under the ribs, although it can extend into the groin and testicles.our left kidney is slightly higher than your right. Pain from the kidneys tends to occur in the flanks or in the lower back just under the ribs, although it can extend into the groin and testicles.