<span>It is the variable in an experiment is not directly altered</span>
Coral reefs are built by coral polyps as they secrete layers of calcium carbonate beneath their bodies. And inside each coral poly lives single-celled algae called zooxanthellae. So basically in simplistic terms, coral polys create coral reefs and algae is in coral polys which also goes into coral reefs when they are made.
About 8.7 Million Species
Yay so happyyyyyyyyyyyyy for youuu
It’s caused by the different density’s in the water
