Question

Define organ? which was the first animal to have organ system? hello ​

Answer 1

An organ is a group of tissues with similar functions. Plant life and animal life rely on many organs that co-exist in organ systems. In the hierarchy of life, organs lie between tissue and organ systems. A tissue is an organizational level between cells and organs. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues. Two or more organs working together in the execution of a specific body function form an organ system, also called a biological system or body system.

The aggregation of different kinds of tissues into organs is a further advancement in the evolution of animals. Organs appear first in the Platyhelminthese (flatworms).

Answer 2

Answer:

platyhelminthese the answer

Explanation:

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