Carbon Dioxide and wastes are transferred for oxygen. The  blood then travels to the left atrium by the pulmonary artery and  then to the left ventricle. The blood leaves the heart by the aorta  to the other parts of the body.. The circulatory system is the organ system that carries substances around our body. There is no such thing as a circulary system.
Overview [edit]. The purpose of the ribosome is to translate messenger RNA (mRNA) to proteins with the aid of tRNA. In eukaryotes, ribosomes can commonly be found in the cytosol of a cell, the endoplasmic reticulum or mRNA, as well as the matrix of the mitochondria.
The synthesis of proteins starts with transcribing the instructions in DNA into mRNA. The mRNA is then carried out of the cell's nucleus into the cytoplasm, specifically into structures called ribosomes. The ribosomes, which contain rRNA, are organelles where protein production occurs. The tRNA transports the amino acids to the ribosomes. The code sequence in mRNA is then translated, and specific proteins are synthesized by stringing amino acids together.