POINT!
WaterIntakeBeforeBasicFeedbackToWaterReabsorption-ENG.jpg

① Water intake decreases plasma osmolarity, and the water reabsorption decreases plasma osmolarity. These effects are in the same direction (red).

WaterIntakeDuringBasicFeedbackToWaterReabsorption-ENG.jpg

② Since these effects are in the same direction (red), negative feedback decreases (blue) the water reabsorption. The plasma osmolarity-decreasing effect of the water reabsorption becomes weaker, and plasma osmolarity returns to normal.

Challenge Quiz

1. Water intake increases decreases plasma osmolarity, and the water reabsorption increases decreases plasma osmolarity. Since these effects are in the same opposite direction, negative feedback increases decrease the water reabsorption.