13. What is the economic
importance of sponges?

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
Some chemical substances by
sponges have -inflammatory,
antibiotic and anti-tumoral and
they are in the production
medicines. Since ancient the
endoskeleton of sponges has had
value, they are as
cleansing implements baths (bath
sponges), wash animals, objects
so on.