Which one of the following substances is actively secreted into the glomerular filtrate of the kidney tubule?

Reabsorption in the tubules of nephrons occurs by the process of

Where does the selective reabsorption of glomerular filtrate take place?

Glucose is reabsorbed from the glomerular filtrate by ......... .

In the distal convoluted tubule $(DCT)$ of the nephrons:

Which of the following statement$(s)$ is/are true?
$(1)$ Urine is hypertonic in the distal convoluted tubule.
$(2)$ When the urine passes into the collecting tubule,it becomes hypotonic.
$(3)$ Urine is isotonic in the proximal convoluted tubule.
$(4)$ Urine becomes more and more hypotonic as it passes through Henle's loop.