Which level is defined as two or more tissues working together to perform a specific function?

• A. Tissue level of organization
• B. Organ level of organization
• C. System level of organization
• D. Cellular level of organization

Answer: (A)

At the organ level, different tissues come together to perform a specific function. A tissue is a group of similar cells carrying out a shared job, but an organ brings together two or more tissue types to accomplish its particular role. For example, a stomach includes epithelial tissue lining the interior, connective tissue to support, and smooth muscle tissue to churn and mix contents—these tissues collaborate to digest food. In contrast, the tissue level would involve just one tissue type doing its job, and the cellular level is about single cells. The systemic level involves multiple organs working together as a whole system. So two or more tissues working together to perform a function describes the organ level of organization.