What Are the Functions of Frog Blood Cells?

A frog's circulatory system differs from that of mammals in two key regards. One, frogs' bodies pump blood using a three-chambered heart, as opposed to the four chambered heart present in mammals (and also birds). Two, a frog's red blood cells contain a nucleus and mitochondria. However, except in one key regard, the blood cells of frogs function like those of other vertebrates (animals whose skeletal system contains a backbone).

  1. Transport

    • All the tissues and organs of a frog's body need oxygen to survive. The hemoglobin in a frog's red blood cells (called erythrocytes) picks up oxygen in the single ventricle of its heart, then transports it to the frog's brain, muscles, etc. Once they have dropped off the oxygen (so to speak), the red blood cells attach to carbon dioxide and carry that gas to the lungs, which expel it back into the air. If the frog is swimming underwater, the blood picks up oxygen through the skin, and if still underwater, takes carbon dioxide back from the skin. Additionally, a frog's blood transports cellular waste from tissues for removal.

    Disease Fighting

    • Like mammals and other vertebrates, a frog's body also produces white blood cells (technically known as leucocytes). These cells help protect a frog from diseases and infections. If a foreign microbe or pathogen enters a frog's body, its immune system can release one of many white blood cell types. Some of these white blood cells engulf (literally, "eat") the foreign microbe and destroy it, while others attach to the side of a foreign microbe and release toxins that kill it. The frog's body can adapt to new environments and situations by producing white blood cells in response to new organisms or toxins that it has not yet encountered.

    Eicosanoid Production

    • When an animal receives a cut, whether to its skin or to an internal organ or tissue, its red blood cells release clotting factors that help block the cut so that less blood can escape. In frogs, the red blood cells also release compounds known as eicosanoids. Eicosanoids play a role in minimizing the cellular damage caused by inflammation. Such inflammation can lead to arteriosclerosis (the clogging of arteries) and heart disease, and also causes asthma. As of 2010, scientists do not understand exactly how this production of eicosanoids works in a frog's blood cells. However, because doctors currently use one form of eicosanoid (called prostaglandins) to treat patients suffering from heart disease, scientists view this function of frog blood cells as a potential treatment for inflammation-related diseases in humans.