The Structure of the Human Urinary System

This note is the first part of multiple that will cover the necessary content in CSEC Biology Syllabus for Section B; Specific Objective 5.4.

The objective of this note is to highlight the structure of the urinary system and the function of the parts. Additionally, an annotated simple diagram of the gross kidney structure is provided.

Introduction:

The following list describes the main parts of the urinary system, and their function(s):

Renal Artery- Carries oxygenated blood, with both useful and not useful substances, to the kidneys.

Renal vein- Carries filtered blood (with harmful/ unnecessary substances removed) away from the kidneys.

Kidneys- Removes waste products and excess substances to form urine. (involved in other processes, for example, blood pressure regulation)

Ureter- Functions to carry urine from the kidneys to the bladder

Bladder- Stores urine until removed from the body.

Urethra- Releases urine previously stored in the bladder to the outside of the body.

Structure of the kidney

The kidney is made up of three main parts: the cortex, medulla and renal pelvis, as reflected in the annotated drawing below.

Importantly, it should be noted that kidneys contain thousands of tiny tubules called nephrons, which span both the cortex and medulla of the kidney.

A subsequent note will look at the nephron in further detail.

Annotated Drawing: