Chapter 2 part 2 Genetics Flashcards
Genes
Contain instructions for making proteins
Genome
inherited characteristic instructions
Proteins
Cellular functions
Mutations
May lead genes to produce abnormal proteins
Chromosomes
23 pairs
Organized genome
Telomeres
Ends of chromosomes that are repeated strands of DNA, cannot replicate without these
Single Nucleotide Polymorphism (SNPs)
Genetic variation
Can be used to track inheritance of disease
Can predict individual response to some drugs
Genome-wide Linkage Study
Searches the families
Genome-wide Association Study
Searches the genome
Programmed Aging Theories
- Believe that aging and death are built into the hard writing of all organisms genetic code
- Longevity is an inherited species-specific trait
Gompertz Function / Curve
- Variations in the life span among species are clearly illustrated when age is plotted against death rates
- Longevity is an inherited species-specific trait (Humans 25%)
- “Aging Genes”
Human Life span
122
How much of longevity in humans is inherited
25%, rest is lifestyle related
Good Genes Gone Bad Theory
Aging genes take over in the post- reproductive years and lead to the ultimate deconstruction of the organism
Replicative Senescence
Loss of ability of cells to reproduce
cellular senescence is 50
Hayflick Limit
The number of times a cell can divide, this varies among species
this does not include cancerous cells
correlated with longevity
Telomere Length
With each replication our chromosomes lose telomeres and when we dont have telomeres left our cells cannot divide
-this is related to age, disease, stress, physical activity, BMI and smoking
FOXO Genes
Groups of genes (Programs)
- FOXO3 variant - related to longevity of muscles, cells, brain
Wear and Tear
Accumulation of damage
Cross- Linking Theory
Helps to explain aging
- Increased cross linking causes tissues to become smaller and stiffer causing them to work harder, this could be dangerous because this can happen in the heart and arteries
- With age there is increased cross-linking of collagen
Collagen
Involved in cross-linking
protein that supports tendons and skin etc.
Glycation
Formation to advanced glycation end-products , AGE
- Exposure to certain kinds of sugar causes glycation
Free Radicals
unstable compounds produced when certain molecules in cells react with oxygen, free radicals seek out and bind to other molecules causing the taken over molecule to loose its functioning
ex- uv light, air pollution, metabolism
Free Radical Theory
believes that aging is the increases activity of these unstable free radical molecules and compromise cell functioning
By product of metabolism
Antioxidants related to this theory
With age its harder to defend against free radicals OR damage from free radicals accumulate overtime
Antioxidants
Chemicals that prevent the formation of free radicals
example- blueberries, black plums, dark chocolate)
Resveratrol
Highly potent antioxidant
example- some evidence that red wine is linked to reduced age-related effects
Caloric Restriction Hypothesis
The view that the key to prolonging life is to restrict caloric intake. Caloric restriction thought to be beneficial in part because it reduces formation of free radicals
Autoimmune Theory
Immune systems attack’s body cells
Error Catastrophe
errors that accumulate with age are the ones that are vital
- accumulation of mutations with age : especially mitochondrial DNA
Conclusions about models of development
we are not meant to live forever
probs not one overarching theory
