The use of ointment for bacterial treatment does not fall into the first line of defence.
The first line of defence are physical (skin,tears, mucus) and chemical barriers( white blood cells also called neutrophils) which are prepared to defend the body against infection. The skin which is one of the first line of defence is a barrier that prevents entry of microorganisms the body. When the first mechanism is not effective especially for pathogens then the second mechanism is activated to get rid of the microorganism.
The use of ointment does not belong to any barrier or defence mechanism this is because it is not a natural way of getting rid of microorganisms within the body system.
In an ocean ecosystem, many types of fish and turtles are herbivores that eat algae and seagrass. Sea urchins are powerful primary consumers in kelp forests.
