Final answer:
Organs are structures made of two or more types of tissues that work together to perform a specific function. Cells form tissues, tissues form organs, and organs form organ systems, each level of organization serving an essential role in the physiology of an organism.
Step-by-step explanation:
Body structures that consist of two or more different types of tissues working together to perform a specific function are known as organs. Examples of organs include the stomach, heart, and brain. Together, these organs perform crucial physiological functions necessary for the survival of an organism.
In the hierarchy of biological organization, individual cells, which are the basic structural and functional units of life, join to form tissues. Tissues are groups of similar cells carrying out related functions. When several different tissues collaborate within a distinct anatomical structure, an organ is formed. Organ systems are composed of multiple organs working cooperatively to carry out complex functions, like the circulatory system, which includes the heart and blood vessels to transport blood throughout the body.