Aging and senescence

Question 1

What is senescence?

Answer 1

Age dependent decline in vital physiological functions

Question 2

What is the disposable soma theory?

Answer 2

Natural selection has caused organisms to have sufficient resources/ repair mechanisms to prevent ageing- at least until the organisms have reproduced and cared for their young

Question 3

What are the senescence factors?

Answer 3

1. Metabolism
2. Reactive oxygen species
3. DNA damage

Question 4

What are factors that increase lifespan?

Answer 4

1. Dietary restriction
2. Environmental stress
3. Signals from the somatic gonad

Question 5

What is the reactive oxygen species?

Answer 5

O2-

Question 6

What causes progeria syndromes?

Answer 6

Nuclear lamina mutations

Question 7

What causes nestor guillermo?

Answer 7

BANF1 mutations- affects the nuclear lamina/ mitosis

Question 8

What does diminished insulin signalling in c. elegans and drosophila cause?

Answer 8

Increase in lifespan

Question 9

How does IGF signalling influence DAF16/ FOXO?

Answer 9

Inhibits FOXO

Question 10

What does decreased TOR activity cause?

Answer 10

Increased lifespan

Question 11

What are the genes downstream of FOXO?

Answer 11

1. Antioxidant genes
2. Chaperones
3. Metabolic genes
4. Antibacterial genes

Question 12

What do sirtuins do?

Answer 12

Prevent ageing

They activate FOXO and the mitochondrial unfolded protein response

Question 13

What activated sirtuins?

Answer 13

NAD- levels decline with age