Scientists add compound P to a dish of cultured human liver cells, and the cells respond. When they add compound Q to an identical dish of liver cells, the cells do not respond.
Which statement explains why the liver cells respond to compound P but not to compound Q?
Q is too large to enter the cells, so it cannot reach the receptor molecules in the cytoplasm.
The cell membranes are fully permeable, so Q passes into the cells without being detected.
The shape of Q does not match the receptor molecules in the membranes of these cells.
Q can only be detected by receptors in a cell wall, and liver cells have no cell wall.
130 exam-style questions on OCR GCSE Biology 1.1 Cell structures, covering 1.1.1 Viewing cells with light microscopes, 1.1.2 Sub-cellular structures and functions, and 1.1.3 Electron microscopy and resolution. Each one has a worked solution and a mark scheme showing where the marks go.