The correct answer is circular. Copernicus and other astronomers before him thought that celestial bodies followed a circular orbital path. Copernicus was a Polish astronomer that concluded that the sun is at rest near the center of the universe and the earth is revolving around it annually. This theory is called heliocentric.
<span>The spicules have an important purpose for loosely constructed animal such as sponge. First of all, spicules give structure which is vital due to loose construction. Secondly, it protects from predators. This is similar to porcupine quills in serving to protect.</span>
<span>C. Weathering breaks down rock and other material</span>
Answer:
The pyrenoid, a dense structure inside or beside chloroplasts of certain algae, consists largely of ribulose biphosphate carboxylase, one of the enzymes necessary in photosynthesis for carbon fixation and thus sugar formation. Starch, a storage form of glucose, is often found around pyrenoids.
