No, they are carbon-based as is all life on earth (as we know it). They do have silica as part of their body, but the main part is carbon.
Silicon is very common in the universe and is shares almost all the qualities of carbon.
Silicon.
they can stretch further
Some people do believe that life can be silicon based but so far its just a theory with no definite answer.
Answerit depends on your definition of life?How helpful, questioning the question that was posed.if you mean silicon based life forms than we havent found any, but we think they exist.
the skeletons can be used as sponges to wash dishes
Although sponges do not have a skeletal system they do have skeleton components that may be made of silicon or lime. A sponge is found in the ocean and is a hollow tube that has several large pores throughout it.
Yes, there is study of silicon zirconia based oxygen analysis. The study of the oxygen precipitation kinetics is an example of the silicon zirconia based oxygen analysis.
Yes, there can be non carbon based life forms; although none yet have been discovered; there is much speculation about the possibility of silicon based life forms due to certain similarities to carbon at the atomic level.
If you're looking for a replacement for carbon in the phrase "carbon-based lifeform" ... there really isn't one. Science fiction sometimes talks about silicon-based lifeforms, but they're not very likely for thermodynamics reasons (silicon would much, much rather bond with oxygen than with another silicon atom, and when that happens you get quartz, not complex molecules capable of supporting life).
Sponges are most sexual!!
Sponges are considered ANIMAL life not plant life. Therefore they do not give off oxygen, they consume it.