The removal of proximal convoluted tubule PCT from the nephron results in lack of reabsorption of high threshold substances frkm renal tubules and obligatory reabsorption of water is also affected leading to more diluted urine. Since PCT is associated with reabsorption of much water by osmosis and glucose and amino acids by secondary active transport and other salts and ions as sodium and potassium by primary active transport.

If the loop of Henle that is long U shaped portion of the tubule that conducs urine with each nephron of kidney.

Main function  is to recover water and sodium chloride from urine. If the loop of Henle will absent then that counter mechanism will not take part  in system so there will be no issues of concentration of urine.