Various parts of mammalian uriniferous tubules (nephrons), play an important role in Urine formation through processes like ultrafiltration, selective reabsorption by active transport, reabsorption by passive osmosis and secretion. While the filtrate flows through different parts of the uriniferous tubules (Numbered 1 - 6 in the diagram given below), not only its volume is reduced but its composition is also considerably changed, due to exchange of materials between the filtrate and the blood of the peritubular capillaries.

From among the numbered parts (1 - 6) in the above diagram, the options are given in a manner that they highlight two aspects separately, i.e., part(s) having columnar epithelial cells with 'brush border', suitable for reabsorption and those parts completely or poorly permeable to water. Select-out the desired options: