Final answer:
The kidneys maintain blood pH and affect hemoglobin's oxygen-binding ability; kidney failure can lead to decreased blood pH and hemoglobin affinity for oxygen. An appropriate hypothesis for testing kidney responsiveness is related to measuring the specific gravity of urine after ADH administration. The kidneys' role in blood flow and sodium excretion is critical for homeostasis.
Step-by-step explanation:
The kidneys serve a vital role in maintaining the body's acid-base balance by removing excess H+ ions from the blood. If the kidneys fail, the blood pH would likely decrease, becoming more acidic because the excess H+ ions would not be adequately removed. This decrease in blood pH would also affect hemoglobin affinity for oxygen; as the blood becomes more acidic, hemoglobin's ability to bind oxygen diminishes, reducing oxygen transport throughout the body.
For an experiment testing kidney responsiveness, an appropriate hypothesis could state: "If the kidney's ability to concentrate urine is impaired due to failure, then the urine's specific gravity will be lower than the normal level, indicating a defect in the reabsorption of water by the kidneys." To assess this, one could measure changes in the specific gravity of urine after administering ADH, since ADH increases membrane permeability to water in the collecting ducts of the nephron, affecting urine concentration.
Regarding handling sodium (Na+), if one wants the kidney to excrete more Na+ in the urine, they would desire an increased blood flow through the kidneys to facilitate that removal. This is part of how the kidneys help in regulating blood volume and pressure and, consequently, the body's homeostasis.
Homeostasis is defined as a self-regulating process by which a living organism can maintain internal stability while adjusting to changing external conditions. Homeostasis is not static and unvarying; it is a dynamic process that can change internal conditions as required to survive external challenges.