x

Why diffusion alone is not enough

Why diffusion alone is not enough

Every living cell needs oxygen and nutrients for metabolism and must remove wastes such as carbon dioxide. Small organisms can often rely on diffusion because most cells are close to the outside environment.

Circulatory system and mass transport Lesson

  1. A Level
  2. /Biology
  3. /Circulatory system and mass transport

Step-by-step lessons covering Edexcel A A Level Biology Circulatory system and mass transport for A Level Biology. Each lesson works through exam-style questions in Paper 1, Paper 2 and Paper 3 format. Build a strong foundation in cell biology and biochemistry early on, since later topics on genetics, ecology and physiology all draw on these core concepts.

Lessons