Final answer:
The macula densa cells are characterized as being denser and taller compared to other cells in the DCT and are crucial for regulating kidney functions.
Step-by-step explanation:
The cells of the macula densa are easy to recognize because they are denser and taller than the other cells of the Distal Convoluted Tubule (DCT). The macula densa cells are found in the part of the DCT forming the juxtaglomerular complex (JGC) and have a critical role in sensing Na concentration in the forming urine. Furthermore, they are involved in the regulation of kidney function by communicating changes in blood volume, pressure, or electrolyte balance to the adjacent afferent and efferent arterioles through the renal juxtaglomerular apparatus.