What are endorphins in the context of the human body?

Endorphins are indeed the body's natural painkillers, primarily produced in the brain. They serve as neurotransmitters, which means they help transmit signals within the nervous system. When released, endorphins bind to the brain's opioid receptors to help alleviate pain and induce feelings of euphoria or pleasure, which is often described as a “runner’s high.” This natural mechanism is part of the body’s response to stress or injury, playing a crucial role in pain management and emotional well-being.

The other options describe different biological functions: hormones for growth and development pertain to substances like growth hormone or thyroid hormones, while neurotransmitters that enhance cognitive function include types such as serotonin or dopamine, which are involved in mood regulation and cognition. Cells that promote immune responses would refer to various immune cells and mediators, like T-cells or cytokines, which are not related to the endorphin's primary functions. Understanding the unique role of endorphins highlights their importance in both physical and mental health.