Final answer:
The gaps between the secondary processes of the podocytes are known as glomerular filtration slits, which play a crucial role in the filtration process of the nephron within the kidney.
Step-by-step explanation:
The gaps between the secondary processes of the podocytes in the kidneys are described as glomerular filtration slits. These filtration slits are critical components of the filtration membrane, which permits the movement of the filtrate from the capillary to Bowman's capsule, thus initiating urine formation. This process takes place in the renal corpuscle, which is part of the nephron - the functional unit of the kidney. The nephron is responsible for filtration, reabsorption, and secretion - the three principal functions for balancing plasma and excreting waste products as urine.