A tumour lies between several brain regions. Some tumour cells extend into healthy tissue.
Why might a surgeon be unable to remove every tumour cell safely?
complete removal could make every remaining brain cell divide uncontrollably
complete removal could make healthy neurones transmit impulses through bone
complete removal could stop sensory receptors from detecting any external change
complete removal could destroy connections needed for normal brain functions
43 exam-style questions on Edexcel GCSE Biology 2.3 The nervous system and brain, covering 2.3.1 Structures and functions of the brain, 2.3.2 Imaging brain function with scanning, 2.3.3 Limitations in treating nervous system damage, 2.3.4 Neurones and impulse transmission, and 2.3.5 Structure and function of a reflex arc. Each one has a worked solution and a mark scheme showing where the marks go.