myoglobin my·o·glo·bin (mī'ə-glō'bĭn)
The oxygen-transporting protein of muscle, resembling blood hemoglobin in function but with only one heme as part of the molecule and with one fourth the molecular weight. Also called muscle hemoglobin.
An iron-containing protein found in muscle fibers, consisting of heme connected to a single peptide chain that resembles one of the subunits of hemoglobin. Myoglobin combines with oxygen released by red blood cells and transfers it to the mitochondria of muscle cells, where it is used to produce energy.
a protein found in the muscle cells of animals. It functions as an oxygen-storage unit, providing oxygen to the working muscles. Diving mammals such as seals and whales are able to remain submerged for long periods because they have greater amounts of myoglobin in their muscles than other animals do.
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