BIOL340 CELL DEATH PATHWAYS EXAM QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTIONS GRADED A++
LATEST UPDATE
cell death introduction
critical for normal physiology
- Embryogenesis
- Tissue homeostasis
Critical for removing damaged or diseased cells (development of cancer)
Unwarranted cell death as a result of disease = Neurodegeneration
Impaired cell death (Cancer or Autoimmune disease)
Neurodegeneration
The loss of particular neurons via apoptosis.
can also prevent cell death
3 main roles of cell death in normal physiology
Embryogenesis, postembryonic development, adult tissue homeostasis
Cell death following tissue injury
,- Ischemia: loss of oxygen to our tissues, causing a change in pH = cell death
- Toxicity: exposure to chemicals causes cells to be damges
- Infection
criteria for a dead cell
Reversible until passing point-of-no return:
1. Lost plasma membrane integrity
2. undergone complete disintegration and/or
3. engulfed by another cell in vivo
Types of Cell death
Apoptosis
Necrosis
Autophagic cell death
Cornification
Apoptosis Vs Necrosis
Apoptosis is very specific cell programmed death
Necrosis not programmed cell death
Apoptosis
- Originally defined by specific morphological features (changes in shape of the cell)
, - Type of programmed cell death
- the cell shrinks itself and doesn't effect any other tissues or cells in close proximity
The dominant form of cell death and the main mechanism by which cells are
physiologically removed from animals
Series of orchestrated morphological and biochemical changes that take place in cells
that have been induced to die
an implosion
Morphological features of Apoptosis
Rounding-up of the cell
•Retraction of pseudopodes (extensions of the cell)
•Reduction of cellular and nuclear volume
•Nuclear fragmentation •Minor modification of cytoplasmic organelles
•Plasma membrane blebbing but intact until late stages
•Engulfment by resident phagocytes, in vivo
Biochemical features of Apoptosis
•Bcl-2 family protein activation (inhibits apoptosis)
•Caspase activation
•Reactive oxygen species overgeneration
•Decreased mitochondrial membrane potential
ANSWERS WITH COMPLETE SOLUTIONS GRADED A++
LATEST UPDATE
cell death introduction
critical for normal physiology
- Embryogenesis
- Tissue homeostasis
Critical for removing damaged or diseased cells (development of cancer)
Unwarranted cell death as a result of disease = Neurodegeneration
Impaired cell death (Cancer or Autoimmune disease)
Neurodegeneration
The loss of particular neurons via apoptosis.
can also prevent cell death
3 main roles of cell death in normal physiology
Embryogenesis, postembryonic development, adult tissue homeostasis
Cell death following tissue injury
,- Ischemia: loss of oxygen to our tissues, causing a change in pH = cell death
- Toxicity: exposure to chemicals causes cells to be damges
- Infection
criteria for a dead cell
Reversible until passing point-of-no return:
1. Lost plasma membrane integrity
2. undergone complete disintegration and/or
3. engulfed by another cell in vivo
Types of Cell death
Apoptosis
Necrosis
Autophagic cell death
Cornification
Apoptosis Vs Necrosis
Apoptosis is very specific cell programmed death
Necrosis not programmed cell death
Apoptosis
- Originally defined by specific morphological features (changes in shape of the cell)
, - Type of programmed cell death
- the cell shrinks itself and doesn't effect any other tissues or cells in close proximity
The dominant form of cell death and the main mechanism by which cells are
physiologically removed from animals
Series of orchestrated morphological and biochemical changes that take place in cells
that have been induced to die
an implosion
Morphological features of Apoptosis
Rounding-up of the cell
•Retraction of pseudopodes (extensions of the cell)
•Reduction of cellular and nuclear volume
•Nuclear fragmentation •Minor modification of cytoplasmic organelles
•Plasma membrane blebbing but intact until late stages
•Engulfment by resident phagocytes, in vivo
Biochemical features of Apoptosis
•Bcl-2 family protein activation (inhibits apoptosis)
•Caspase activation
•Reactive oxygen species overgeneration
•Decreased mitochondrial membrane potential
