The heart is an example of an organ.
Protein
Proteins are the most versatile
macromolecules in living systems and they play important roles in essentially
all biological processes. Protein makes up the capsid of a virus. The infective
extracellular form of a virus known as a virion contains at
least one unique protein synthesized by specific genes in the nucleic acid of
that virus. In almost all viruses, at least one of these proteins forms a shell
(called a capsid) around the nucleic acid. Certain viruses also have other
proteins internal to the capsid. Some of these proteins act as enzymes during
the synthesis of viral nucleic acids.
Answer:
A protein molecule present in the RBCs, which helps in the transportation of oxygen from the lungs to the different parts of the body and brings back carbon dioxide, that is, collected from different parts of the body back to the lungs is known as hemoglobin.
The general features of hemoglobin are that it comprises four molecules of protein in the form of globulin chains. In adults, the molecules of hemoglobin comprise two beta-globulin chains and two alpha globulin chains, while in infants and fetuses, the beta chains are least found, and is substituted by two gamma chains.
Each globulin chain comprises an essential iron-containing compound porphyrin, which is termed as heme. Together both iron and heme play an essential role in circulating oxygen and carbon dioxide in the blood. This iron gives the red appearance to the blood.
