
Apoptotic cells in C. elegans
Source

Example of H&E tissue biopsy Source
When students are asked to compare and contrast two types of cell death: necrosis and apoptosis, the same answers come back:
Apoptosis is programmed cell death.
Necrosis is premature cell death.
All the right things are said but when we then look at a biopsy, they are unsure if necrotic areas are showing necrosis or apoptosis. They don’t seem to be getting the underlying concepts.
So, what do you think of the following ‘car death’ analogy?
Scenario 1: Apoptosis
You are driving along the highway and notice a warning light and there is a strange noise in the car. You pull over and a tow truck takes away the car. The car is finished but there was minimal or no damage to the surrounding cars and road. The car had just come to the natural end of its life. The car can go to the scrap yard, recycling useable pieces.
Scenario 2: Necrosis
You are driving along a busy highway and something external hits the car – bullet or lightning – and the car explodes. Not only has the car had a ‘premature death’ but it may have damaged the cars around it and/or the road. This can disrupt traffic as well as leave a permanent mark. The crew that comes in to clean up the bits is analogous to the immune system (this last sentence going too far?).

Ferrari on fire
Source
What do you think? Does the analogy work? Do you think it helps people see the underlying differences between the two processes?
This was a quick out-of-thin-air analogy so I accept that it might not work and I welcome all suggestions!
LisaM says
love it! I don’t know enough about necrosis to say if the comment on the immune system clean up is “too far”, but the rest of it makes it all so clear.
Shu Ito (@shuito82) says
Nice analogy!
Although, there are instances in apoptosis where external factors nudge a cell to die. In the car analogy, it would be akin to a saboteur stuffing a potato in the exhaust before you started driving…something external that tipped a cell to die.
genegeek says
Thanks. I tried to show the external with lightning or bullet but I think the potato works better.
Cynthia Purves (@Purvesc) says
Well in terms of explaining the science the analogy works really well for me because I have experience with the tow truck and salvage yard as well as being the crew that comes to clean up the bits after an accident. Now I understand necrosis and apoptsis very well.
genegeek says
Thank you for the nice words.