UNIT OVERVIEW

Your body makes waste every second. When cells break down food for energy, they produce carbon dioxide. When proteins are broken down, they produce a toxic substance called ammonia. If these wastes build up, they will poison you.

Excretion is the process of removing these waste products from your body. This unit focuses on how your kidneys, lungs, liver, and skin work together to keep your blood clean and your body in balance.

What you will learn:

• The difference between excretion and egestion
• How different organs remove different wastes
• The structure of the urinary system (kidneys, ureters, bladder, urethra)
• How the nephron filters blood and makes urine
• How hormones (ADH and aldosterone) control water and salt balance
• Kidney diseases and treatments (dialysis and transplants)
• How to dissect and identify parts of a mammalian kidney

What you should already know:

• Cellular respiration produces carbon dioxide (Grade 10)
• Homeostasis means keeping conditions inside the body stable (Grade 10)
• Diffusion, osmosis, and active transport (Grade 10)
• Proteins are broken down by deamination (Term 2: Animal Nutrition)
• How blood circulates through the body (Grade 10)

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