Question

Insulin is a hormone that regulates blood sugar by binding to its receptor, insulin receptor tyrosine kinase. How does insulin’s behavior differ from steroid hormone signaling, and what can you infer about its structure?

Short answer

Insulin is polar as a result it does not enter the cell while the steroid is smaller in size and non-polar it easily crosses the membrane and form a hormone-receptor complex and directly communicate with cellular DNA to regulate transcription.

Step-by-step solution

Step 1. Introduction

Insulin is a blood sugar-regulating hormone that binds to its receptor tyrosine kinase which is an enzyme-linked transmembrane receptor.

Step 2. Explanation

Tyrosine kinase receptors are embedded in the plasma membrane and insulin attach to the outer surface of the receptor to initiate intercellular signaling cascades. Usually, Steroid hormone enters the cell to bind with intercellular receptors as it is small and non-polar. These intercellular hormone-receptor complexes directly communicate with cellular DNA and regulate transcription. However, insulin does not cross the plasma membrane it could be because of its large size or polar.