Mcb 135K Lecture 16 (Apoptosis)

Front 1

True or false. Apoptosis is a phenomenon only seen in single cells and unicellular organisms?

Back 1

False. Apoptosis can be seen in multicellular organisms and even in plants.

Front 2

True or false. Apoptosis is evolutionarily conserved.

Back 2

True.

Front 3

The stages of classic apoptosis are:

Back 3

1) Death signal (can be internal or external).
2) An irreversible execution.
3) Engulfment by nearby macrophages.
4) Degradation.

Front 4

The C. elegan genes used to control apoptosis in nematodes are genes originally belonging to which group of animals?

Back 4

Mammals.

Front 5

Four reasons why apoptosis is important in embryogenesis.

Back 5

1) Morphogenesis-to get rid of excess cells.
2) Selection-to get rid of non functional cells.
3) Immunity-get ride of dangerous cells.
4) Organ size-again, to eliminate excess cells.

Front 6

How is apoptosis important in adults? Give three examples of this.

Back 6

Tissue remodeling-used to get rid of cells no longer needed. 1) Cells in the prostate die via apoptosis after decreased production of testosterone in
males.
2) Apoptosis is the mechanism in which involution (non-lactating, no-pregnant) in mammary glands is driven to start.
3) Maintain organ size and function.
4) Steroid immunosuppressants use apoptosis to kill off lymphocytes that abound in an infection site during the process of recovery.

Front 7

Cells lost in apoptosis (especially those in organs are replaced by what mechanism?)

Back 7

Cell division.

Front 8

Too much apoptosis can lead to ____ and ______, etc.

Too little apoptosis can lead to ______ and ____, etc.

Back 8

Neuro-degeneration and thin skin.

Cancer, atherosclerosis, etc.

Front 9

Neuronal death can be caused by ___, _____, and ____.

Back 9

1) Loss of proper connections.
2) Loss of proper growth factors.
3) Damage (esp. oxidative damage).

Front 10

Neuronal dysfunction and damage are mainly caused by _____, and/or _______.

Back 10

1) Loss of synapses.
2) Loss of cell bodies.

Front 11

Synaptosis is reversible/irreversible in neuro-degeneration and what about apoptosis?

Back 11

Synaptosis is reversible, but apoptosis is not .

Front 12

What are three famous neuro-degenerative disorders that may be linked to apoptosis?

Back 12

1) Huntington's Disease.
2) Parkinson's Disease.
3) Alzheimer's Disease.

Front 13

Regarding apoptosis, high levels of _____ proteins and/or low levels of _____ proteins can lead to cancer.

Back 13

High levels of anti-apoptosis proteins and/or low levels of pro-apoptosis proteins.

Front 14

What gene is the master controller of the senescent and apoptotic response to damaged cells?

Back 14

The p53 gene.

Front 15

Most cancer cells are defective in what response controlled by the p53 gene in most normal cells?

Back 15

The apoptosis response.

Front 16

With the elderly, too much or too little apoptosis is seen?

Back 16

Both.

Front 17

Too little apoptosis leads to _____ in the elderly. Too much apoptosis leads to ________.

Back 17

Too little (defective signals?) apoptosis leads to accumulation of dysfunctional cells and signs of hyperplasia (pre-cancerous lesions) are present.

Too much (accumulated oxidative damage?) apoptosis leads to tissue degeneration.

Front 18

Apoptosis is self induced cells death or induced by factors outside the cell?

Back 18

Apoptosis is self induced cell death, similar to suicide.

Front 19

Necrosis is a passive/active process?
What about the root of its causes? (physiological or pathological?)
What happens?
Aftermath?
Inflammation (yes or not)?
Externally or internally induced?

Back 19

Necrosis is an passive process.
Pathological.
Swelling, lysis.
Dissipates.
Inflammation.
Externally induced.

Front 20

Apoptosis is an active or passive process?
Pathological causes or physiological?
What happens?
Aftermath?
Inflammation?
Externally or internally induced?

Back 20

Apoptosis;

Active.
Physiological or pathological.
Condensation, cross linking.
Phagocytosed.
No inflammation.
Internally or externally induced.

Front 21

For mitotic catastrophe, is it a passive or active process?
Pathological or physiological causes?
What happens?
Aftermath?
Inflammation?
Externally or internally induced?

Back 21

Passive.
Pathological.
Swelling, lysis.
Dissipates.
Inflammation.
Internally induced.

Front 22

Does apoptosis occur in ALL multi-cellular organisms? Why?

Back 22

Yes. It is crucial for survival.

Front 23

Which stages of apoptosis are reversible?

Back 23

Up to the commitment to die after the death signal is received.

Front 24

Cells lost by apoptosis are replaced how? What restricts how many times this can occur?

Back 24

Via cell division. Limited replicative potential-after a number of times, tissue renewal potential declines.

Front 25

In both the physiological and pathological pathways of apoptosis, what are the four necessary steps, what organelle is always involved?

Back 25

Mitochondria is always involved.
Mitochondrial signals--> Caspace cleavage cascade---> Orderly cleavage of proteins and DNA---> Cross linking of cell corpse; Engulfment.