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How do germs enter the human body through the nose, mouth, and broken skin?

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Health monitoring — human disease The routine monitoring of blood pressure levels is an important part of assessing an individual's health. Blood pressure provides information about the amount of blood in circulation and about heart function and thus is an important indicator of disease.

The human body is protected by robust external barriers that prevent most germs from causing disease. When these defenses are compromised, pathogens can gain entry through specific routes.12

Broken Skin

Your skin acts as a primary mechanical barrier, utilizing a tough outer layer of cells and protective secretions like fatty acids and enzymes to neutralize bacteria. Germs typically only bypass this defense when the skin is breached by an opening, such as a cut, scrape, or severe burn, which allows pathogens to enter the body directly.231

Nose and Mouth

The nose and mouth are entry points for germs that travel through the respiratory or digestive tracts. These areas are lined with mucous membranes, which secrete mucus to trap particles and pathogens. In the respiratory tract, tiny hairlike projections called cilia help sweep trapped germs out of the body. If pathogens bypass these defenses, they may multiply within the tracts or enter the bloodstream to cause systemic infection. In the digestive tract, the stomach provides an additional layer of protection by secreting hydrochloric acid, which is capable of killing many ingested microbes.14526