Chromosomes are structures found in the nucleus of most cells. The plural of nucleus is nuclei. organ<span> A </span>group<span> of different tissues that </span>work together<span> to carry out a particular function, eg heart and lungs. </span>organ<span> system A </span>group of organs that work together to complete<span> a specific function.</span>
Organ systems. For example the mouth,stomach, small and large intestines make up the digestive system. So the organs work together to make up an organ system.
