Module Directory

This module will provide an introduction to the study of genetics and evolution.

The aim of this module is:

• To provide an introduction to the study of genetics and evolution.

By the end of this module, students will be expected to be able to:

Evolution

1. Describe how natural selection can explain adaptation (in the context of inherited variation and over-production of offspring, with limited resources).


2. Describe examples of natural selection acting as the mechanism for evolution (Galápagos finches and drug resistance).


3. Describe how evolutionary theory can explain observations of the fossil record, anatomical and molecular homologies and biogeography.


4. Describe the differences between homology, analogy and homoplasy.


5. Explain how phylogenies can be constructed using morphological and molecular characters.


6. Describe informatic algorithms to compare sequences (nucleic acids and proteins).


7. Explain how genomes contain evidence of their evolutionary history.


8. Explain how population genetics allows us to understand how evolution can act at the level of the gene in populations.


9. Explain what is meant by the gene pool and how the Hardy-Weinberg equilibrium model can be applied to calculate allele frequencies in populations.


10. Identify and explain the assumptions underlying the Hardy-Weinberg model.


11. Calculate allele frequencies and expected genotype frequencies from a sample of observed genotype frequencies.


12. Explain how mutation and sexual reproduction lead to variation in the gene pool.


13. Define the terms random genetic drift and gene flow.


14. Explain how the three key factors of natural selection, genetic drift and gene flow contribute to evolution.


15. Identify and describe the differences between directional, stabilising and disruptive selection and describe an example of each.


16. Explain the meaning of natural selection, in relation to the phrase "survival of the fittest" and to the idea of differential transmission of alleles.


17. Explain how heterozygote advantage and frequency dependent selection can maintain unfavourable alleles in populations.


18. Explain the meaning and evolutionary outcomes of sexual selection, including intrasexual selection and intersexual selection.


19. Describe the biological species definition and explain some limitations of the biological species definition in practice.


20. Identify the different types of reproductive isolating mechanisms and describe examples of each.


21. Identify the key features of allopatric and sympatric speciation and explain each process.


22. Explain the key features of a hybrid zone and its possible outcomes with regard to the process of speciation, including reinforcement, fusion or stability.


23. Describe how genes control the body plans of animals and plants.


24. Explain the conservation of genes controlling body plans and how small changes in these genes can lead to striking variation in form.

Genetics

1. Draw diagrams to show the segregation of chromosomes during all the stages of meiotic cell division.


2. Explain the differences between meiosis and mitosis.


3. Explain the importance of random assortment and crossing over in relation to inheritance.


4. Explain how the normal karyotype is maintained during sexual reproduction.


5. Describe the effects of errors in meiosis on the karyotype (aneuploidy and polyploidy).


6. Define the terms used in describing Mendelian inheritance.


7. State Mendel’s Laws and apply these to predict the outcome of single and two factor crosses.


8. Explain the nature of dominance and recessiveness.


9. Describe the multiple alleles of the ABO blood group system.


10. Explain the basis of genetic linkage and the consequences of crossing-over for linked genes (recombination).


11. Construct a simple genetic map using the data from experimental crosses and explain why this may not correspond exactly to the physical map.


12. Explain the basis of sex-linkage and the inheritance of sex-linked genes.


13. Describe how X-inactivation occurs in mammals.


14. Describe sex determination in humans and fruit flies.


15. Explain how the relationship between genotype and phenotype can be complicated by interactions between genes (e.g. epistasis) and by the environment (e.g. temperature sensitive mutations).


16. Explain the inheritance of quantitative or polygenic traits and the influence of the environment.

Molecular Biology

1. Molecular basis of heredity and mutation.


2. Describe the structure of the key macromolecules involved in the storage, replication and expression of genetic information: DNA, RNA and proteins.


3. Explain the experimental evidence for DNA as the genetic material.


4. Describe the key features of the genetic code including the start and stop codons.


5. Explain the effects of single base mutations: silent, missense and nonsense mutations; reading frames and frameshift mutations.


6. Explain the evidence for semi-conservative DNA replication.


7. Describe the events that take place at the replication fork and the components involved.


8. Explain the differences in the synthesis of the leading and lagging strands.


9. Describe how mutagens cause damage to DNA and the mechanisms used to repair the damage.


10. Describe how mutations and gene function can lead to heredity patterns.

Gene expression and its control.

1. Describe the process of RNA synthesis (transcription) and explain why gene expression is regulated.


2. Explain the control of the E. coli lac operon by the repressor protein and the operator and promoter sequences.


3. List some additional eukaryotic mechanisms for regulating expression.


4. Describe the events which take place at the ribosome during protein synthesis (initiation, elongation and termination).


5. Explain the role of tRNAs and aminoacyl-tRNA synthetases in protein synthesis.

DNA based techniques

1. Describe the methods of gel electrophoresis and blotting (Southern and northern).


2. Explain the use of DNA hybridisation in detecting nucleic acids.


3. Describe the method of bacterial plasmid-based gene cloning.


4. Describe the molecular tools (restriction enzymes and DNA ligase) used in this work.


5. Explain the methods used to construct libraries of gene sequences.


6. Describe the map-based and shotgun approaches to DNA sequencing.


7. Explain how synthesis-based sequencing methods work and contrast them with other approaches to sequencing describe how high-throughput sequencing can be applied in research and industry.


8. Describe the techniques of PCR and DNA fingerprinting.


9. Explain how PCR and fingerprinting can be applied in forensics, medicine and population genetics.


10. Describe the steps involved in making a transgenic plant.


11. Describe the process of animal cloning.


12. Describe some applications for gene cloning and gene editing in biotechnology and medicine, and explain some of the environmental and social issues relating to the ethics of gene technologies.

Genome biology primer

1. Describe the variation in genome size and gene number in genetic model organisms.


2. Describe the goals of the human genome project and be aware of some of the resources and applications developing from it.

Laboratory

1. Carry out the practical work and coursework associated with this course.


2. Carry out a BLAST search and determine a phylogeny using open access online bioinformatics tools.


3. Extract DNA at a quality suitable for basic downstream applications, such as genome sequencing.


4. Describe the techniques used for purifying and separating nucleic acids.


5. Describe how Nanopore sequencing identifies individual bases.


6. Carry out a restriction enzyme digest and construct a restriction enzyme map.

Nothing in biology makes sense except in the light of evolution". This quote from evolutionary biologist Theodosius Dobzhansky sums up the importance of understanding evolution, and how genetic information is transmitted.

This module will also look at genetic variation and genes in populations and consider the role of natural selection in adaptive evolution, followed by mechanisms of speciation and adaptive radiation. This brings us up to date with recent studies of phylogenetics and the evolution of genes and genomes, together with the history of all organisms.

The module then moves on to the structure and function of DNA and the expression of the information contained in the genome. This is followed by modern methods in gene cloning and the applications of this technology. Finally, we move on to the transmission of genetic information from one generation to the next by the process of cell division and the principles of Mendelian inheritance.

This module will be delivered via:

• One 1-hour lecture per week.
• One 1-hour lecture on directed learning material.
• One revision class before the MCQ exam.
• One revision class before the summer exam.
• Two 3-hour practical sessions.