Master GCSE Biology

MS1 (1 mark):

- Different forms of a gene that can occur at the same locus on a chromosome.

MS2 (2 marks):

- Possess two different alleles for the same gene on homologous chromosomes.

- Can produce gametes with either allele.

MS3 (3 marks):

- Independent assortment of chromosomes during metaphase I.

- Crossing-over during prophase I creates new gene combinations.

- Separation of homologous chromosomes during anaphase I.

MS4 (1 mark):

- Mutation

MS5 (2 marks):

- Bacteria with mutated genes giving antibiotic resistance survive and reproduce.

- Resistant bacteria pass on their resistant genes to offspring.

- Frequency of resistance gene increases in population over time.

MS6 (4 marks)

- Potential to cure genetic diseases/treatments.

- Genetic discrimination/eugenics/designer babies.

- Long-term effects on human evolution/genetic diversity.

MS7 (1 mark):

- Genetically identical individuals produced asexually.

MS8 (2 marks):

- Selecting individuals with desirable traits for breeding.

- Repeated breeding over generations to pass on favourable alleles.

- Increased crop yield/quality.

MS9 (3 marks)

- Starts with kingdom, phylum, class, order, family, genus, species.

- Groups organisms based on shared characteristics/evolutionary relationships.

- Species is the fundamental unit of classification.

MS10 (1 mark):

- Observable characteristics controlled by genotype and environment.