Question

Write short notes on sponges? And its significance. 

Answer 1

• Absence of nervous and muscular tissue indicates that sponges must have been one of the earliest forms in the course of evolution.
• Absence of tissues indicate that the body organisation would have been at cellular level only without cells forming compact tissues.
• Further this also indicates that sponges do not show locomotion since they have no means of evaluating the surrounding because they lack muscular tissue. 
• They are sedentary since they lack muscular tissue