The lining of the proximal convoluted tubule $(PCT)$ is made up of $.......$.

High threshold substances are the substances which can be

Where does the selective reabsorption of glomerular filtrate take place?

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.

.......... is absent or highly reduced in cortical nephrons.

Reabsorption in the tubules of nephrons occurs by the process of