Mucus is a protective substance secreted from many areas of the body. The mucins in mucus can act as a selective barrier, lubricant, or viscous substance depending on their structure. So how well do you understand mucus in the body?

The color of the mucus from your nose when you have a runny nose can indicate many health-related problems. In particular, if you blow your nose with yellow mucus and feel pain, this is a sign that your respiratory system is working abnormally. More specifically, what does a yellow runny nose remind you of about your health and is it serious?