Question

In tissue level of organisation

• A. the cells are arranged as loose cell aggregate
• B. the tissues are grouped to form organs
• C. the cells performing the same function are arranged into groups
• D. the tissues are grouped to form organ systems

Answer 1

The correct option is C the cells performing the same function are arranged into groups

Body organisation is one of the criteria based on which animals have been further divided into phyla. Body organisation may be cellular, tissue-level, organ-level or organ system level.

In tissue level of organisation, all the cells performing similar functions group together to form a unit called tissue. Groups of cells join together to form a tissue and this kind of organization is seen in some animals, where the tissues perform specific functions. Hydra and jellyfishes have tissue level of organisation.

In cell aggregate body plan, the body consists of an aggregate of the cells with almost no differentiation and are not organised into tissues or organs. Example: Sponges.

Several tissues join together to form organs, which perform specific functions and this type of organization is called an organ level of organization. Several organs join together to form an organ system, such as the respiratory system, circulatory system, etc. Such a level of organization is called organ system level of organization.