In pea plants, the allele for purple flowers (PPP) is dominant over the allele for white flowers (ppp).
A scientist crossed a homozygous purple-flowered plant (genotype PPPPPP) with a homozygous white-flowered plant. All resulting F1 F_1\,F1 offspring had purple flowers.
State the genotype of the homozygous white-flowered parent plant.
Two of the F1 F_1\,F1 offspring plants (both with genotype PpPpPp) are crossed. Complete the genetic diagram (Punnett square) below by determining the missing genotypes of the offspring.
Male gamete: PMale gamete: pFemale gamete: PPP(i)Female gamete: p(ii)(iii) \begin{array}{c|c|c} & \text{Male gamete: } P & \text{Male gamete: } p \\ \hline \text{Female gamete: } P & PP & \text{(i)} \\ \hline \text{Female gamete: } p & \text{(ii)} & \text{(iii)} \end{array} Female gamete: PFemale gamete: pMale gamete: PPP(ii)Male gamete: p(i)(iii)Identify the genotypes for (i), (ii), and (iii).
State the expected ratio of purple-flowered plants to white-flowered plants in the offspring of this cross in its simplest form.
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.