This comprehensive lesson introduces students to the structure and function of the excretory system and its essential role in maintaining internal balance. Learners investigate how metabolic waste is removed from the body, explore the functions of the kidneys, and examine the processes involved in blood filtration and urine formation.

Students develop an understanding of the urinary system’s major structures before exploring the anatomy of the nephron, including the glomerulus, Bowman’s capsule, Loop of Henle, and collecting duct. The lesson explains the biological processes of ultrafiltration and selective reabsorption, helping students understand how water, salts, glucose and urea are regulated within the body.

The resource includes labelling activities, structure-function matching tasks, and opportunities to apply knowledge through annotated diagrams.

Learning Objectives

Students will:

Explain the functions of the excretory system.
Link the structures of the excretory system to their functions.
Describe the production and removal of urea.
Explain the process of ultrafiltration within the nephron.
Explain the process of selective reabsorption.
Identify the major structures of the urinary system and nephron.
Included in this Resource

Full lesson PowerPoint

Introduction to the excretory (urinary) system

Urea production and excretion

Functions of the excretory system:
Blood filtration
Reabsorption
Waste removal

Urinary system anatomy:
Kidneys
Ureters
Bladder
Urethra
Renal artery
Renal vein
Aorta
Vena cava

Structure and function matching activity
Kidney and nephron anatomy

Detailed coverage of:
Cortex
Medulla
Glomerulus
Bowman’s capsule
Tubules
Loop of Henle
Collecting duct

Ultrafiltration process explained step-by-step
Selective reabsorption process explained

Labelling and annotation activities

Suitable For
KS4 Biology
GCSE Biology
Applied Science
Health and Social Care
Anatomy & Physiology
BTEC Science
Access to HE Science
Post-16 Biology courses
Skills Developed
Scientific knowledge and understanding
Anatomical identification
Structure-function relationships
Understanding of homeostasis
Diagram interpretation
Scientific vocabulary development
Recall and retrieval practice

This engaging lesson provides students with a clear understanding of how the excretory system removes waste, regulates body fluids and maintains homeostasis through the specialised functions of the kidneys and nephrons.

Keywords: excretory system, urinary system, kidney, nephron, ultrafiltration, selective reabsorption, Bowman’s capsule, glomerulus, Loop of Henle, collecting duct, urine formation, urea, homeostasis, renal system, GCSE Biology, anatomy and physiology, Applied Science, Health and Social Care.