When people talk about glands, what do they mean? The answer is many different things. Glands are important organs, you have a variety of them all over your body, and though many of them are small, each produces something important.
Some glands make something that is released from the body — like saliva, sweat, or tears. And if you're a girl, the mammary glands in your breasts could someday make breast milk to feed a baby.
Other glands release hormones (say: hor-mones), which are substances inside your body that tell it how to work and how to grow. Glands that do this are part of the endocrine (say: en-doh-krin) system. Puberty — body changes that turn a kid into an adult — depend on the endocrine system.
Still other things that we call "glands" are part of your immune (say: ih-myoon) system. They release substances that help you fight off illnesses and, if you are sick, help you get better. When you have a bad cold and your neck glands are swollen, that is your immune system in action.