← 3.2 Human Excretory System

Wastes from skin, lungs and kidneys

Integrated Science · Grade 7 · about 40 minutes

Skin excretes excess salts and water in sweat. Lungs excrete carbon IV oxide. Kidneys excrete excess salts and water in urine. Search, then lock the map.

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  • 7 sections of explanation, worked examples and diagrams
  • 1 practice task with hints and worked answers
  • A quiz that marks itself as you go
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