Answer:
Tissues are defined as an integrated group of cells that share a common structure and a common function (for example, nervous tissue or muscle tissue). Sponges are described as lacking true tissues. True tissues are present in Cnidaria, flatworms, and all higher animals.
Step-by-step explanation:
Tissues are defined as an integrated group of cells that share a common structure and a common function (for example, nervous tissue or muscle tissue). Sponges are described as lacking true tissues. True tissues are present in Cnidaria, flatworms, and all higher animals.