Oxygen is a vital part of life that affects different living beings in a number of ways. Typically, we think of air simply as something that we must have circulating into and out of our bodies at a fixed rate. Similarly, all living things must require some form of respiration in order to survive, right?
Insects do breathe as a way to ensure that oxygen is distributed throughout their entire body. The cells of the insect, in particular, require a rich oxygen supply in order to keep it alive and properly functioning.
The remainder of this article will explore respiration in various insect species and explain the basics of the process of respiration. Additionally, this article will delve into the ways in which different types of insects carry out the process of breathing and how exactly an insects’ body may utilize oxygen.
Do Insects Need Oxygen?
The short answer is yes. In order to perform the bodily functions that are vital to the survival of each and every insect, oxygen must be taken in regularly. The way in which insects intake oxygen is fairly similar across all species.
All animals, including insects, need oxygen in order to survive. If oxygen is not present, the living cells that make up the insect will die. Unlike humans, insects are incapable of carrying oxygen through the blood. Instead, tracheae act as a network system that allows oxygen to reach every part of the insect. In some cases, the oxygen may not reach every part of the insect, however.
One shortcoming of the tubing system, however, is the limit to the length of each trachea. For example, in dragonflies, this method of respiration through diffusion may fail to deliver sufficient oxygen supply to every body region. Similarly, oxygen tends to slow down its travels as its journey lengthens.
Generally, larger insects are at greater risk of complications stemming from a lack of oxygen supply. This is a direct result of an evolutionary shortcoming that explains the generally small scale of the anatomy of many insects.
How Do Insects Intake Oxygen?
While insects need oxygen just like humans do, the way in which they take in oxygen and distribute it throughout the body is very different. Unlike humans, insects do not have lungs, nor do they have a traditional circulatory system.
Small holes called spiracles can be found covering the entire surface of each insect’s body. Spiracles are capable of opening and closing in order to take the appropriate level of oxygen in to keep the remaining oxygen out. Muscle contractions dictate the frequency at which spiracles open and close.
The respiratory system of an insect is very simple in nature. Rather than pumping oxygen through the lungs, a simple internal distribution of oxygen coats the inside of the insect’s body. This is accomplished thanks to the interior tracheal system, which acts as a network to distribute oxygen throughout the body. As a direct result, carbon dioxide is expelled from the body as a waste product.
The interior of an insects’ body acts like a sponge. Like a sponge, spiracles act as the holes that allow air and moisture into the body. Carbon dioxide is released from the body as a result as the insect “exhales.”
Due to their low metabolic rate, insects are capable of shutting down their major body systems while still surviving for a number of days. Insects are in control of their less than traditional respiratory systems. As a result, insects may periodically pause their “breathing” by closing off their spiracles, depriving their tracheae of oxygen.
In doing so, the cells awaiting a necessary supply are left without oxygen temporarily. This is a way for the insect to protect its tissue from overexposure to oxygen.
In What Ways Do Insects’ Bodies Utilize Oxygen?
The internal bodily structures of insects consist mostly of an air-filled tube system. Insects’ bodies work just as hard to take oxygen in as they do to keep some out. Due to the low metabolic rate in insects’ bodies, they may periodically “hold their breath” in order to prevent themselves from taking in too much oxygen.
While oxygen is vital to the survival of all living things, including insects, too much could potentially damage the fragile tissue of the insects’ body.
In instances where an insect may inhabit a hostile, dry, desert-like environment, spiracles can voluntarily close and remain closed for extended periods of time. In doing so, any moisture that is already present will remain trapped inside of the insect’s body until the muscles relax and reopen the spiracles.
Spiracles may remain closed in certain environments for multiple reasons. The most common reason relates to the necessity to lower internal oxygen levels to a safer level physiologically speaking. As a direct result, gas exchange is halted, causing the ideal oxygen and moisture levels to remain consistent until oxygen is taken in once again.
How Can Hemoglobin Help Insects to Breath?
In oxygen-poor conditions, insects from the Chironomidae family, in addition to a few other insect species, can trap oxygen within hemoglobin. Bloodworms (Chironomid larvae), for example, are capable of releasing oxygen from hemoglobin.
In releasing oxygen from hemoglobin, insects are able to gain temporary relief from potential oxygen deprivation. This backup oxygen supply is capable of releasing enough oxygen to power the insect through moving from an oxygen-poor environment to a significantly more desirable oxygen-rich environment.
Much like the tracheal gill system working as a snorkel unit, bubbles of air can also provide insects with the necessary oxygen levels. In insects such as aquatic beetles, a temporary breath of air is provided when these “bubbles” release oxygen. In doing so, the insect is essentially carrying its own personal internal oxygen tank.
How Do Aquatic Insects Breathe?
Aquatic insects carry out breathing processes that vary from that of the traditional land insect. On land, oxygen fills the air at roughly 200,000 parts per million. Underwater, however, oxygen is not as readily available at around 15 parts per million.
So how do insects carry out respiration in aquatic environments? The answer is quite simple. A number of species of insects have a tracheal gill system that aids them in obtaining the oxygen that they need in order to survive. Gill systems operate in a similar manner to snorkel sets that humans may use in order to breathe underwater.
For insects that only spend a small portion of their life cycle underwater, the tracheal gill system operates just as it would in insects who permanently reside in aquatic environments. The gills act as small extensions of the insect’s exterior that can take in significant amounts of oxygen.
To answer the question at hand, yes, insects do breathe. Insects breathe in oxygen and release carbon dioxide as a waste product. Because they do not have lungs, insects do not carry out a respiration process that is identical to that of humans.
Insects are designed to take in oxygen under the specific conditions to which they are most frequently exposed. For example, grasshoppers are among the most mobile, high-energy insects in existence. When a grasshopper is at rest, its body is still taking in oxygen at the same rate as flying or leaping from one leaf to another.