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any idea or hints for this question pleaseeee

Homeostatic control of temperature is an example of negative feedback. Atherosclerosis is an example of positive feedback.

Outline the sequence of events that lead to the development of atherosclerosis and explain why it is a positive feedback loop.

- atherosclerosis process i know
- I am struggling with 'why it is a positive feedback loop'

Someone please help me :frown:
no idea
I'm not too up to scratch on atherosclerosis myself, but maybe the diagram in figure 2 of this article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6738649/ will help?
If they're not exactly the same as the steps you know, then try to identify a step in the atherosclerosis formation that promotes another step.
Original post by zuzannasendor18
Homeostatic control of temperature is an example of negative feedback. Atherosclerosis is an example of positive feedback.

Outline the sequence of events that lead to the development of atherosclerosis and explain why it is a positive feedback loop.

- atherosclerosis process i know
- I am struggling with 'why it is a positive feedback loop'

Someone please help me :frown:


Development of atherosclerosis increases blood pressure because artery walls lose elasticity. High blood pressure (from atherosclerosis) causes damage to endothelium resulting in more plaque/atheroma ... aggravates atherosclerosis.
Reply 4
Original post by thomas.rhett
Development of atherosclerosis increases blood pressure because artery walls lose elasticity. High blood pressure (from atherosclerosis) causes damage to endothelium resulting in more plaque/atheroma ... aggravates atherosclerosis.

This answer is partly true, however, it ignores the fact that atherosclerosis is an inflammatory process.
Reply 5
Original post by zuzannasendor18
Homeostatic control of temperature is an example of negative feedback. Atherosclerosis is an example of positive feedback.

Outline the sequence of events that lead to the development of atherosclerosis and explain why it is a positive feedback loop.

- atherosclerosis process i know
- I am struggling with 'why it is a positive feedback loop'

Someone please help me :frown:

I usually reserve the term feedback loops for physiological processes, like control of temperature, which you’ve mentioned. The best example of a positive feedback loop is during labour. As the baby’s head pushes on the cervix, this signals to the posterior pituitary to release more oxytocin, which increases uterine contractions, and so the cycle repeats.
I wouldn’t have called atherosclerosis a positive feedback loop, although it’s certainly a vicious cycle.
In atherosclerosis, there is some insult or trauma to the endothelium (lining of blood vessels) which allows LDL to enter the inner lining of the arterial wall. This LDL is oxidised, which is pro-inflammatory, which recruits inflammatory cells. These inflammatory cells release reactive oxygen species and pro-inflammatory mediators which recruits more inflammatory cells, and so the cycle continues.

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