Mechanism of Hormone Action

The video explains how hormones in the human endocrine system recognize and act on their target cells through specific receptors. It distinguishes between steroid and non-steroidal hormones, detailing their mechanisms of action. Steroid hormones, like estrogen, are lipid-soluble and act by entering cells and influencing gene expression. Non-steroidal hormones, such as epinephrine, are lipid-insoluble and rely on transmembrane receptors and second messengers like cAMP to exert their effects. The video also touches on how these processes are regulated and the impact of external factors like toxins.

How does the hormone epinephrine initiate a response in liver cells?

What physiological effects are caused by the action of epinephrine during the fight or flight response?

Describe the role of the enzyme phosphodiesterase in the regulation of cAMP levels.