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Led by Gregor Mendel Simulacrum
The fifth module of the OCR GCSE Biology A course — the genome, sexual and asexual reproduction, genetic crosses, natural selection and evolution. Hosted by Gregor Mendel Simulacrum.
Led by Gregor Mendel Simulacrum
The question
The language of genetics — gamete, chromosome, gene, allele, dominant, recessive, homozygous, heterozygous, genotype, phenotype — and how the genome interacts with the environment to produce the characteristics of an organism. Covers how all variants arise from mutations and how genetic variants in coding and non-coding DNA can affect phenotype.
Outcome
The student can define the key terms of genetics, explain how the genome and environment interact to influence phenotype, and describe how genetic variants affect phenotype. (Molecular genetics)
Sub-units
Led by Gregor Mendel Simulacrum
The question
Two strategies for passing on genetic information — asexual reproduction (fast, identical offspring, no variation) and sexual reproduction (slower, genetically unique offspring, variation). Covers the terms haploid and diploid, and the role of meiosis in halving the chromosome number and generating genetic variation.
Outcome
The student can explain the advantages and disadvantages of sexual and asexual reproduction and explain how meiosis produces haploid gametes. (Reproduction and meiosis)
Sub-units
Led by Gregor Mendel Simulacrum
The question
How to predict the outcomes of single gene inheritance using Punnett squares — homozygous and heterozygous crosses, dominant and recessive alleles, ratios and probabilities. Covers sex determination in humans (XX/XY), the recognition that most phenotypic features involve multiple genes, and Mendel's founding contribution to genetics through his pea-plant experiments.
Outcome
The student can predict the results of genetic crosses using Punnett squares, describe sex determination, and explain Mendel's contribution to genetics. (Classical genetics)
Sub-units
Led by Gregor Mendel Simulacrum
The question
How populations change over time through natural selection — variation, inheritance, differential survival, and change in inherited characteristics over generations. Covers the evidence for evolution (fossils, antibiotic resistance), classification systems including molecular phylogenetics, and the independent work of Darwin and Wallace in developing evolutionary theory.
Outcome
The student can explain how evolution occurs through natural selection, describe the evidence for evolution, and describe the contributions of Darwin and Wallace. (Evolutionary biology)
Sub-units