Which statement correctly describes the location of alleles of the same gene and their expression in a diploid organism exhibiting codominance?
Alleles of the same gene occupy different loci on sister chromatids, and in codominance, only the dominant allele is expressed in the phenotype of a heterozygote.
Alleles of the same gene occupy the same locus on homologous chromosomes, and in codominance, both alleles are expressed in the phenotype of a heterozygote.
Alleles of different genes occupy the same locus on homologous chromosomes, and in codominance, a heterozygote displays a phenotype that is a blending of both alleles.
Alleles of the same gene occupy the same locus on non-homologous chromosomes, and in codominance, the expression of one gene masks the expression of another gene at a different locus.
97 exam-style questions on OCR GCSE Biology 5.1 Inheritance, covering 5.1.1 The genome, 5.1.2 Environment and phenotype, 5.1.3 Variants and mutations, 5.1.4 How genetic variants influence phenotype, 5.1.5 Asexual and sexual reproduction, 5.1.6 Haploid and diploid, 5.1.7 Meiotic cell division, 5.1.8 Single gene inheritance, 5.1.9 Predicting single gene crosses, 5.1.10 Sex determination, 5.1.11 Multiple gene inheritance, and 5.1.12 Development of our understanding of genetics. Each one has a worked solution and a mark scheme showing where the marks go.