Final answer:
The afferent arteriole is the blood vessel that feeds the glomerulus with blood from the cortical radiate artery, and it plays a critical role in the filtration function of nephrons within the kidney.
Step-by-step explanation:
The blood vessel directly feeding the glomerulus with blood from the cortical radiate artery is the afferent arteriole.
Blood enters the kidney at the renal hilum and the renal blood supply begins with the branching of the aorta into the renal arteries. The renal arteries branch into segmental arteries, which then divide into interlobar arteries. These interlobar arteries further split at the junction of the renal cortex and medulla to form arcuate arteries. From the arcuate arteries, the cortical radiate arteries radiate out and these in turn branch into many afferent arterioles that then supply the nephrons with blood.
The afferent arteriole is the last segment in the series of branching arteries before reaching the nephron's capillaries, specifically the glomerulus, which is involved in the filtration of blood.