"When the thirst center goes on alert because things are too salty and the body needs water to dilute the salt, that’s when you start to feel thirsty. The kidneys help dilute the salt too by slowing down urine production and conserving water. The constant balancing of salt and water in the body helps maintain the right amount of water in our cells and in the bloodstream. That controls our blood pressure."
- - - The mouth is where the river flows into another body of water and there is least oxygen here. The river slows down here and that decreases dissolve oxygen.
