Organ and Organ System
In multicellular organisms, all basic functions like digestion, respiration, and reproduction are performed by groups of cells organized into tissues. A tissue is defined as a group of similar cells working together to perform a particular function. The human body has four basic types of tissues: epithelial, connective, muscular, and neural.
These tissues combine to form organs such as the heart, lungs, and kidneys, where each organ is composed of one or more types of tissues. When two or more organs work together, they form an organ system. An example is the digestive system, which includes organs that work together to digest food and absorb nutrients.
The section introduces the morphology and anatomy of frogs, which represent a group of vertebrates. Morphology refers to the structure of organisms, while anatomy deals with the internal structure. Frogs exhibit a division of labor by organizing their cells, tissues, and organs, ensuring efficient and coordinated functioning critical for survival.