LIFE AND DEATH IN EUKARYA

Question 1

what is senescence?

Answer 1

• detoriation with age

Question 2

viewpoints to age related diseases?

Answer 2

1. evolutionary viewpoint - aging is a consequence of passing period of reproductive usefulness. SO CANNOT BE SELECTED AGAINST IN CLASSIC EVOLUTIONARY THEORY
2. biochemical viewpoint - aging is highly regulated process that determines a period of reproductive usefulness.

Question 3

link between mitochondria and senescence?

Answer 3

• site of respiratory chain
• some molecular oxygen

Question 4

why do cells die?

Answer 4

• no obvious reason
• neurons are irreplicable
• cancer cells = immortal

Question 5

what is the hayflick limit?

Answer 5

• telomeres on chromosome shorten with each cell division as a result of ROS damage

Question 6

how many ways can cells die?

Answer 6

1. apoptosis
2. autphagy
3. necrosis

Question 7

what is apoptosis?

Answer 7

• activation of caspases - by binding of various activator proteins.
• destruction of mitochondria
• destruction of gDNA
• formation of apoptotic bodies.

Question 8

what is the role of mitochondria in apoptosis?

Answer 8

• releases cytochrome c from respiratory chain and apoptosis - induced factor
• triggers first stages

Question 9

what is the role of caspases in apoptosis?

Answer 9

• cytochrome c and AIF all involved in keeping with origins of mitochondria

Question 10

what is autophagy?

Answer 10

• organelles degraded by lysosomal pathway

Question 11

what is the 3 checkpoints for cell cycle?

Answer 11

1. g2 checkpoint
2. spindle assemble checkpoint
3. g1 checkpoint

Question 12

what is the g2 checkpoint?

Answer 12

• cell checks size and how DNA replication has gone.

Question 13

what is the spindle assembly checkpoint?

Answer 13

• late mitosis
• checks for chromosomal attachment to mitotic spindle

Question 14

what is the gq checkpoint?

Answer 14

• checks for cell size, nutrient and growth factor availability and DNA damage.