Ants don’t have blood. Instead, they have hemolymph, a similar circulatory fluid. Unlike blood however, hemolymph consists of hemocytes and does not contain red blood cells and hemoglobin.
In this article we’ll look deeper into the question, “do ants have blood?”, as we discuss what hemolymph is, its functions, and its differences from blood. We’ll also discuss the ant circulatory system and see how it’s different from ours.
What Is Hemolymph?
Hemolymph is a circulatory fluid in the bodies of arthropods that’s equivalent to the blood found in vertebrates. It’s made of fluid plasma which contain free-floating cells called hemocytes, water, organic compounds, and inorganic salts. Unlike blood, hemolymph is often clear, but sometimes greenish or yellowish in color, as it doesn’t contain red blood cells and hemoglobin.
Functions Of Hemolymph
Hemolymph also functions similarly to blood as it too serves as the medium of transport which carries different substances such as hormones and nutrients to the cells. Unlike blood though, hemolymph isn’t used for gas transport due to the lack of hemoglobin. Not like it should anyway, as ants have a tracheal respiratory system which bypasses the need for gas transport.
Apart from being a mode of transport, the different components found in hemolymph also serve various functions. Water for example, serves as a useful reserve which allows ants to withstand desiccation.
The free-floating hemocytes on the other hand, primarily consist of phagocytes which serve to protect the ant’s body against invasion. It develops immunity against bacterial diseases and helps overcome certain parasites.
Lastly, hemolymph also serves important mechanical functions. It is the means by which pressure is transferred throughout the body and assists in the process of molting. It’s volume also serves to maintain body size.
The Ant Circulatory System
Ants have an open circulatory system which differs greatly from the closed circulatory system that we have. Open circulatory systems have hemolymph instead of blood, and this hemolymph flows freely within body cavities where it makes direct contact with tissues and organs. In contrast, blood in a closed system is always contained within vessels.
The primary purpose of the ant circulatory system is to facilitate the circulation of hemolymph which as discussed serves a number of purposes including nutrient transport and defense against diseases.
To do so, ants use a dorsal vessel, a long tube that runs through the thorax and the abdomen. On the posterior section of this vessel are intake valves called ostia which bring hemolymph into the vessel. From there, contractions allow the hemolymph to flow to the anterior end of the dorsal vessel where a simple tube called the aorta pushes the hemolymph towards the head.
As the hemolymph emerges from the aorta, it bathes the organs and muscles of the head and then makes its way back into the open body cavity until it reaches the abdomen and re-enters the heart. From there, the process repeats.
Do Ants Have Hearts?
Ants have a heart called the dorsal vessel which as discussed is a long tube that runs through the ant body. This vessel has two regions, the pumping organ in the abdomen which pushes the hemolymph from the hind end of the body, and the aorta which extends forward and allows the hemolymph to reach the head.
Do Ants Have Lungs?
Ants don’t have lungs as they’re too small to accommodate them along with their supporting parts. Instead, ants make use of a tracheal respiratory system to breathe. This system is characterized by spiracles and a network of tubes called trachea which deliver oxygen directly to the cells of the body.
Summary: Do Ants Have Blood?
Ants technically don’t have blood. Instead they have a clear, sometimes yellowish or greenish, circulatory fluid called hemolymph. Unlike blood, hemolymph does not contain hemoglobin and isn’t used for gas transport. It’s also used in open circulatory systems wherein the fluid flows freely, while blood is used in closed circulatory systems.
As circulatory fluid, hemolymph facilitates the transfer of nutrients and hormones inside the ant body. It also, by nature of its composition, has other functions including defense against infections and serving as a water reserve to prevent dedication.