= Major calyx
A <major calyx> is a larger branch of the <renal calyx> network that receives <urine> from converging <minor calyx> passages and carries it toward the <renal pelvis>. The terms “minor” and “major” describe positions in a branching drainage system, not a comparison between small and large <nephrons>.<Kidneys by the National Cancer Institute>[internal anatomy: convergence of minor calyces into major calyces]{ref}
A useful physical analogy is a branching funnel: several small collecting openings feed a shared passage, and shared passages lead toward a common outlet. In the <kidney>, the anatomical sequence is specific: a <renal papilla> discharges into a <minor calyx>, which joins a <major calyx> before the <renal pelvis>. The actual branching arrangement can be examined in a sectioned specimen rather than inferred from the outline of the organ alone.<Longitudinal section through Kidney by the Manipal Museum of Anatomy and Pathology>[specimenEXC002: labeled calyceal drainage]{ref}
If two incoming branches supply steady flows $q_1$ and $q_2$, their receiving passage carries $q_1+q_2$ when no fluid accumulates. This <mass balance> explains why a <major calyx> pools information from upstream regions: a measured change in its contents does not uniquely locate the source of that change.
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