Topic 8 - Learning Outcomes

Topic 8.1: Establishing the body plan Describe techniques used for studying embryonic development. Outline evolutionarily conserved mechanisms that together underpin the development of complex multicellular organisms. Outline the main stages in the development of vertebrates.

Topic 8.2: Generating diversity and complexity Describe how the mesoderm becomes segmented.         2. Outline the evolutionary changes in the Hox gene cluster, and how these have contributed to body plan specialisations

Topic 8.3 : What is ageing and why does it happen? Give examples of the range of lifespans of some animal species. Define what is meant by the term ‘biological ageing’. Describe briefly examples of factors that can affect lifespan. Give examples of the species that are used to study lifespan and ageing. Outline how lifespan experiments are performed, and give examples of control experiments that are necessary for the analysis of lifespan. Interpret data from lifespan experiments. Explain the difference between evolutionary and mechanistic theories of ageing. Briefly describe the main evolutionary theories of ageing.

Topic 8.4: Mechanisms of ageing – molecules and organelles Briefly describe the different forms of molecular damage that may occur during ageing. Provide examples of some of the agents that may mediate oxidative damage, and describe where they may originate. Summarise the different cellular protective mechanisms and give examples of some protective molecules expressed by cells. Outline the types of experiment that have been performed to elucidate the roles of free radicals in ageing. Briefly describe how genome instability, telomere shortening, epigenetic and nuclear changes may contribute to ageing. Give examples of premature ageing syndromes. Outline how mitochondrial changes can contribute to ageing. Briefly describe how a breakdown in proteostasis or organelle ‘housekeeping’ can influence ageing.

Topic 8.5: Mechanisms of ageing – cells, signalling and systems Explain the phenomenon of cellular senescence; outline its possible causes, and how it has been studied. Describe the changes in stem cells and their environment that occur during ageing, and how these may impact upon stem cell function. Briefly summarise the evidence that the IIS signalling pathway plays a key role in ageing. Outline how intercellular communication may change during ageing, and thus lead to broader effects in mammals. Interpret data relating to age-associated changes in the above areas. Give examples of how study of non-laboratory organisms may add to our understanding of ageing.

Topic 8.6: Ageing and the microbiota Explain the term ‘microbiota’, and give examples of where microbiota occur. Describe why it is important to consider the gut microbiota when studying the development and ageing of an organism. Summarise factors that may cause a change in the gut microbiota. Provide examples of how gut microbiota may influence longevity in Caenorhabditis elegans.