3) Give one function of Meibomian gland:​

abnormal gland function. As we know, the meibomian glands secrete the meibum responsible for the formation of the tear film's outer layer. The meibum aids in reducing the evaporation of tears from the front surface of the eye, increasing the surface tension and forming an optically superior tear meniscus.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.