The three main parts of a eukaryotic cell is Cell membrane, nucleus, and other organelles. Cell membrane surrounds the cytoplasm of a cell. Nucleus is a dense organelle in most eukaryotic cells. Other organelles is the largest organelle such as the nucleus and vacuoles, they are easily visible with the light microscope. Hoped I helped. :)
In cells use oxygen to release energy stored in sugars such as glucose. In fact, most of the energy used by the cells in your body is provided by cellular respiration.
