Limestone contains calcium carbonate which comes from animals that have shells, it already has carbon. Other sources are ocean animals which create shells that combine both carbon and calcium. Their dead bodies also release carbon to the ocean. Limestone is also known as a sedimentary rock that has carbon. Outside the ocean, limestone emits the carbon and becomes part of the carbon cycle. In addition to this, limestones are widely used by people becomes a part of the carbon cycle. Its component is present on asphalt, animal feed.
Blood cells are produced in the bone marrow and the bone marrow is part of the skeletal system. So the answer would be skeletal system<em>. </em>
The Hershey and Chase experiment concluded the same by labeling the DNA of the parents with phosphorous and found out that the DNA of the offspring also bear phospho- labeled DNA, which established the fact that DNA is the heritable information source. So, your answer is B.
Well, Euglena is in phylum Euglenophyta, and Paramecium is in phylum Ciliophora. You can verify that with a quick Google search.
<span>Does that sort of narrow it down? :)</span>