Urine formation is involved in water and electrolyte balance in vertebrates. Which of the following statements is the most correct regarding urine formation?

Question

Quizplus · Accepted Answer

Reabsorption in the kidneys is highly selective, meaning that only ions and molecules that are needed by the body are reabsorbed back into the bloodstream. This helps to maintain proper electrolyte and fluid balance in the body. The formation of pre- urine is not selective, as it is a non-concentrated filtrate of blood, and is later modified through selective reabsorption and secretion in the renal tubules. Water is also not actively pumped across membranes, but rather follows osmotic gradients created by ion movements. Malpighian tubules are structures found in insects and other arthropods, not in vertebrates.

Urine Formation Is Involved in Water and Electrolyte Balance in Vertebrates