It protects your immune system and Mucus collects bacteria and prevents it from entering your blood stream. It is carried away by your lymphatic system. It is one of the many first line immune defenses that body uses to fight disease. Drugs that limit mucus formation keep this defense mechanism from working and put more burden on the other natural defenses.
The purpose of slime coating is to protect the fish against disease, infection and minor damage.
Mucus
Infection.
Submucosal glands that secrete mucus are a characteristic of the respiratory system. These glands help to keep the airways moist and trap foreign particles to protect the lungs from damage or infection.
The nose normally secretes mucus to help protect the lining, moisturize the air and trap particles (including infections). When the nose is irritated (by infection, allergies or other issues) it produces more mucus. "Boogers" are just dried mucus.
mucus infection
Mucus in the nose traps incoming particles like dust and bacteria, preventing them from entering the respiratory system. In the windpipe, mucus helps to trap and remove harmful substances that are breathed in, protecting the lungs from infection and irritation. The mucus also contains enzymes and antibodies that help to neutralize and eliminate pathogens.
nose: airways are lined with cells that can produce mucus in which dust and microbes get trapped.
Most of the time ulcers are caused by stress which would come from the inside.... the mucus wouldnt matter... like, you can build a castle for protection but if the problems on the inside then the castles of no use... get it?
small amounts...ruptured (abrasions on the) mucus membranes from irritation. shouldn't be a big deal. Large amounts, could be a ruptured blood vessel from strain and irritation..also not that big a deal, but it could also be a sign of an infection, depends on what color your mucus is. if it's brown, like poop brown, you may need to go to the doc for antibiotics, this generally means a bacterial or fungul infection. Green means infection too, but over the counter meds should suffice. Yellow or white then it's ok, just your body upping the normal mucus amounts in your sinuc cavieties to protect from further infection while your body fights the cold already in your system. Mucus acts just like natural vasoline to moisten and protect the inside of the body constantly being exposed to the elements.
When you are sick, your body's immune system responds to the infection by increasing mucus production. Mucus helps trap and flush out pathogens from the body, helping to protect your airways and respiratory system. This increased mucus production is a defensive mechanism to help eliminate the virus or bacteria causing the illness.
Sinus infection.