Final answer:
The dark urine color is a sign of dehydration, a consequence of consuming salty potato chips and not drinking enough water, which causes the body to conserve water. The kidneys conserve water by concentrating the urine, an excretory process to maintain homeostasis.
Step-by-step explanation:
Understanding Urine Color and Osmosis
When consuming a salty snack like potato chips, your body requires more water to balance the high salt intake. As a result, your body tries to conserve water, leading to a reduced urine output, and when you do dehydrate, the urine that is excreted is highly concentrated with metabolic wastes, which results in a darker color, strongly indicative of dehydration. The potato chips contribute to an increase in blood sodium levels, which then triggers osmosis — the movement of water from areas of low solute concentration to areas of high solute concentration across a semipermeable membrane.
During osmosis in your body's cells, water moves to try and equalize solute concentrations on both sides of the cell membranes. When the body is low on water due to high dietary sodium intake (as with potato chips) or sweating, it will start to conserve water. This results in less water being excreted, and since urine is a mix of water and waste products, less water means more concentrated urine. Therefore, your dark urine color is a sign your body has conserved water to maintain homeostasis and deal with increased solute concentration.
Excretion is a method the body uses to maintain homeostasis, especially regarding water balance. The kidneys play a crucial role by altering the concentration of urine. They conserve water when the body is dehydrated, which is why, after eating salty foods and not drinking enough water, urine can become significantly darker in color.