What are free radicals?

Free radicals are highly reactive molecules that possess unpaired electrons, which makes them unstable. This instability drives them to seek stability by reacting with other molecules in the body, including lipids, proteins, and DNA. This reactive nature can lead to cellular damage, contributing to various processes such as inflammation, aging, and the onset of certain diseases, including cancer and neurodegenerative disorders.

In the context of free radicals, their reactivity is significant because when they interact with cellular components, they can cause oxidative stress, which is an imbalance between free radicals and antioxidants in the body. This oxidative stress can lead to a cascade of cellular events that may ultimately harm the cells and tissues, making the identification of free radicals as damaging agents important in understanding pathophysiological processes.

This is why the answer highlighting the highly reactive nature of free radicals and their potential to cause cell damage is correct. Other descriptions fail to capture the critical role that these unstable molecules play in cellular harm and the broader implications for health and disease.