First of all, you might want to spell DEFENSE correctly.
no because it is in the body
External defenses - Includes skin and mucous membranes. Internal defenses - Includes phagocytic cells, inflammatory responses, and antimicrobial proteins.
The first two lines of defense in the immune system, which include physical barriers (like skin and mucous membranes) and innate immune responses (such as inflammation and phagocytosis), are considered nonspecific because they respond to all pathogens in the same way, regardless of their specific identity. These defenses act immediately upon recognition of harmful agents, employing general mechanisms that do not tailor their response to specific threats. This broad-spectrum approach helps to provide immediate protection against a wide range of infections before the more specialized adaptive immune response is activated.
These lines are perpendicular: _|
Earl's-defense is a system of fortifications for protection.
The gastroderm is the inner layer of cells that lines the gut or digestive cavity of cnidarians such as jellyfish and corals. It is involved in digestion, absorption of nutrients, and in some cases, defense mechanisms.
4
when the first and the second lines of defense have already been overcome.
Fever
Railway tracks electrical lines
Did you mean "real world examples of parallel lines"? If so, railroad tracks are a perfect example.
In the nasal cavity, foreign bodies are primarily managed through several lines of defense. The initial response includes physical barriers such as nasal hairs and mucous membranes that trap and filter out particles. If a foreign object is lodged, the body may trigger sneezing or increased mucus production to expel it. In cases where these mechanisms fail, medical intervention may be necessary to safely remove the object.