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.
Cell membrane proteins have a number of different functions. Structural proteins help to give the cell support and shape. Cell membrane receptor proteins help cells communicate with their external environment through the use of hormones, neurotransmitters, and other signaling molecules. Transport proteins, such as globular proteins, transport molecules across cell membranes through facilitated diffusion.