Different tissues combine to form what structural unit?

Different tissues combine to form organs, which are functional units of the body. Each organ is made up of several types of tissues that work collaboratively to perform specific functions. For example, the heart consists of muscle tissue for contraction, connective tissue for support, and epithelial tissue for lining the chambers and controlling the flow of blood. This combination of various tissue types allows the organ to carry out its unique role effectively.

In contrast, while cells are the basic building blocks of life and the smallest units of structure and function, they do not combine to form tissues directly. The oral cavity is a specific structure within the body that contains several types of tissues, but it itself is not formed solely by the combination of different tissues. Systems are larger organizational units that consist of multiple organs working together, but they are a higher level of complexity than what is defined by the combination of just tissues. Therefore, the correct focus here is clearly on organs, where tissues come together to form distinct structural units with defined functions.