Ageing and Disease Flashcards
What does aging describe in biology
he result of a build-up of cellular and molecular damage over time that leads to a gradual decline in physical and mental abilities
Give some examples of diseases which are more predominant in aging populations
Cancer/ coronary heart disease/ dementia (Alzheimer’s is a type of dementia)
What is progeroid syndrome ?
A genetic disorder which is characterised through features mimicking physiological aging.
What is apoptosis?
programmed cell death - required to prevent cancer
What is longevity?
How long an organism lives for
What is senescene?
time-related deterioration
What is semelparity?
Group of organism which live up until they reproduce
Give some hallmarks of ageing.
Cellular senescence /mitochondrial dysfunction/ epigenetic alterations/ genomic instability / stem cell exhaustion …
What is genome integrity?
The ability to maintain the genome or all its DNA in a cell during cell division
What are some mechanisms used by cells to prevent DNA damage?
DNA REPAIR - // SCANNING FOR DNA DAMAGE-
What is the relationship between insulin signalling and longevity ?
calorific restriction promotes longevity (and increases insulin sensitibity)// mutants which partially block insulin signalling promote longevity
What is the role of animal models in investigating age?
Using a worm as a model the A.C. elegan mutation was found to double life expectancy
What is the role of the P53(“guardian of the genome”)?
A tumour repressing gene which activates apoptosis / senesce and DNA repair in response to DNA damage/ telomere dysfunction/ oncogene activation
What is the role of telomerase?
A reverse transcriptase which grows telomers (end units of a gene which are not often replicated and are therefore lost)
What is cellular senescene?
a tumour repressor which prevents the accumulation of excess cells by stopping cell division
What is the biological function of amyloid precursor protein(APP)?
To bind other proteins on the surface of cells or help other cells attach to one another//
What is proteolytic processing?
the cleavage of specific peptide bonds within a protein precursor changing the conformation of the protein
What proteolytic processes amyloid precursor protein?
APP is cleaved by Beta and gamma secretase, with beta gamma secretase being harmful as it cleaves the peptide at length 40-42, this creates aggregation and therefore cell death and dementia
What is the association between Amyloid precursor protein gene variants and familial forms of Alzheimer’s disease?
Different enzymes cleave the APP at different lengths, gamma secretase cleaves the peptide at length 40-42 amino acids, this is harmful, creating aggregation, cell death and therefore dementia
What is proteostasis?
The process by which cells maintain the balance of functional proteins (protein homeostasis )
Give examples of diseases which are associated with protein folding issues?
ALZHEIMER’S -> formation of amyloid plaques and neurofibrillary tangles // PARKINSONS-> lewy bodies are formed from x -synuclein
What are the 3 main types of proliferation of cells ?
Mitotic cells (continuously dividing~)// post-mitotic or quiescent (low or no division can e stimulate) // fixed post mitotic (no division under a stimulus)
What are the two types of late onset alzhiers disease?
- FAMILIAL - autosomal dominant, involves the APP and PSEN1 // 2. SPORADIC -> general population
What is the role of proto-oncogenes?
cell proliferation