An embolus is a piece of a clot that lodges in a blood vessel, blocking the flow of blood through that vessel. Most emboli are composed of hydrophilic substances that can be dissolved into the water of blood relatively easily. However, two types of emboli--air emboli and fat emboli--are particularly dangerous and difficult to treat because both are composed of hydrophobic substances. Why do you think hydrophobic emboli are more difficult to break apart in the water-based environment of blood