CAPE Biology Unit 2 · 2014 · Paper 1 · Question Q30

Which of the following correctly identifies the substances moving across the membranes at points 1, 2, 3 and 4?

1. (A)1: \text{K}^+; 2: \text{Ca}^{2+}; 3: \text{Ca}^{2+}; 4: \text{Na}^+
2. (B)1: \text{K}^+; 2: \text{Na}^+; 3: Acetylcholine; 4: \text{Ca}^{2+}
3. (C)1: \text{Na}^+; 2: \text{K}^+; 3: \text{Ca}^{2+}; 4: Acetylcholine
4. (D)1: \text{Na}^+; 2: \text{Ca}^{2+}; 3: Acetylcholine; 4: \text{Na}^+

This question uses a figure or table from the paper — you'll see it when you practise.