In tomato plants, the allele for purple stem (PPP) is dominant to the allele for green stem (ppp).
Two heterozygous tomato plants (PpPpPp) are crossed.
Complete the Punnett square below to show the possible genotypes of the offspring by identifying the genotypes represented by the letters AAA, BBB, CCC, and DDD:
GametesPpPABpCD\begin{array}{c|c|c} \text{Gametes} & P & p \\ \hline P & A & B \\ \hline p & C & D \\ \end{array}GametesPpPACpBDState the probability (as a percentage) that an offspring will have a green stem.
A grower plants a batch of 12 seeds from this cross. Explain why there might not be exactly 3 offspring with green stems.
76 exam-style questions on AQA GCSE Biology 6.1 Reproduction, covering 6.1.1 Sexual and asexual reproduction, 6.1.2 Meiosis, 6.1.3 Advantages and disadvantages of sexual and asexual reproduction, 6.1.4 DNA and the genome, 6.1.5 DNA structure, 6.1.6 Genetic inheritance, 6.1.7 Inherited disorders, and 6.1.8 Sex determination. Each one has a worked solution and a mark scheme showing where the marks go.