Which of the following is the correct process for reabsorption in the proximal tubule?
1) Sodium is transported out first, then water follows the electrical gradient, and then chloride ions are reabsorbed.
2) Water is transported out first, then sodium follows the electrical gradient, and then chloride ions are reabsorbed.
3) Chloride ions are reabsorbed first, then water follows the electrical gradient, and then sodium is transported out.
4) Water is transported out first, then chloride ions are reabsorbed, and then sodium follows the electrical gradient.