Insights:

Thermal uncoupling is a biochemical process that facilitates non-shivering thermorigenesis, of particular importance in neonates.

T3 (thyroid hormone) and noradrenaline work together to shift mitochondrial activity (in brown adipose tissue) away from making more ATP to producing more heat. This occurs independent of muscle activity.

Image sources:

https://www.frontiersin.org/articles/10.3389/fphys.2014.00479/full

http://biochemistry.utoronto.ca/research/research-areas/molecular-cell-biology/

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