Globular proteins are water soluble proteins that fold and coil into a tertiary structure in a way that positions hydrophobic R-groups inside the molecule and hydrophilic R-groups on the surface of the molecule in contact with the aqueous environment usually surrounding proteins.Globular proteins include insulin which is a hormone transported in the bloodstream and haemoglobin, the main component of red blood cells.Enzymes are globular proteins. They are soluble and their 3D shape allows them to bind to their substrates and catalyse reactions.
The action of hormones depends on their ability to bind to their receptors due to their having a shape complementary to the shape of the receptors.