An Organelle is the structure present within the cell and is tinier than the cells. They are microscopes and are visible when viewed under an electron microscope. Example: Nucleus, chloroplast, lysosomes, cell membranes, etc. Organs are formed when a group of tissues having the same origin and function join together. Tissues are a group of similar kinds of cells performing the same function. Organs are larger than tissues and visible to the naked eye. Example: human organs like stomach, heart, brain, lungs, liver, eyes, muscles, etc. From here we can conclude that organs are larger and bigger than the organelles.