Answer:
Steroids
Step-by-step explanation:
Signal molecules are produced by signalling cells and bind to the target cells to initiate a response. Steroids come under the category of small hydrophobic signalling molecules. They are lipids and hence fat soluble.
They are derived from cholesterol thus share the chemical structure with it. They have a hydrocarbon skeleton in the form of four fused rings. They can have different types of functional groups attached in different manner to the carbon skeleton. Example of steroid hormones are estradiol and testosterone.