Two plant crosses test competing explanations of inheritance. A distinct-unit model predicts one short offspring for every three tall offspring. A permanent-blending model predicts no short offspring. The parents in both crosses have the same genetic combinations.
Table
| Cross Tall offspring Short offspring | :---: :---: :---: | P 606 194 | Q 294 106 |
| ------------------------------------------ | ----------------------- | --------------- | --------------- |
Which statement correctly combines a calculation with an evaluation of the evidence?
The combined short percentage is 25.4%; agreement supports distinct units without demonstrating their physical location.
The combined short percentage is 25.0%; agreement supports distinct units without demonstrating their physical location.
The combined short percentage is 25.0%; agreement supports distinct units and demonstrates their physical location.
The combined short percentage is 25.4%; agreement supports distinct units and demonstrates their physical location.
40 exam-style questions on AQA GCSE Biology 6.3 The development of understanding of genetics and evolution, covering 6.3.1 Theory of evolution, 6.3.2 Speciation, 6.3.3 The understanding of genetics, 6.3.4 Evidence for evolution, 6.3.5 Fossils, 6.3.6 Extinction, and 6.3.7 Resistant bacteria. Each one has a worked solution and a mark scheme showing where the marks go.