Animals are either osmoregulatory or osmoconformers. Kidneys produce urine and collect it in renal pelvis. Blood in renal vein has lower blood pressure than artery
Kidneys lie in retroperitoneal space between peritoneum and posterior abdominal wall. Left kidney located at T12-L3 vertebrae, right lower due to liver. Each kidney weighs 125-175g in males, 115-155g in females. Covered by fibrous capsule, renal fat pad, and renal fascia
Renal medulla is the innermost part of the kidney. Contains 10-18 cone-shaped renal pyramids. Pyramids form striped appearance from parallel nephron segments. Pyramids' apex (papilla) points inward towards pelvis
Kidneys consist of cortex, medulla, lobes, and lobules. Each kidney contains 1.3 million nephrons, which are the functional units. Kidneys control water balance, eliminate waste, and regulate blood pressure
Nephrons are the functional units of the kidney, containing over one million in each kidney. The nephron consists of glomerulus surrounded by Bowman's capsule. The renal tubule includes proximal convoluted tubule, loop of Henle, and distal convoluted tubule
Nephron is the basic functional unit of kidneys, consisting of glomerulus and tubules. Each kidney contains about millions of nephrons, ranging from 35-55 mm long. Nephron consists of renal corpuscle and renal tubule