Animals with SKIN respiration

In order to live, animals need take in oxygen and remove waste gases. Throughout the animal kingdom we can find a large number of animals, adapted to living in different environments and with different types of life and food. All this means that the animals have developed four types of breathingMainly: respiration through the lungs, respiration through gills, respiration through gaps, and skin respiration.

In this lesson from a TEACHER we will see the Characteristics and examples of animals with skin respiration, the simplest breath of the four. But do not be fooled, despite its great simplicity this system is very effective for some animals, and complements the main respiration of other animals that you could not even imagine!

Index

1. Characteristics of animals with cutaneous respiration
2. Cutaneous respiration in invertebrates
3. Skin respiration in fish
4. Cutaneous respiration in amphibians
5. Skin respiration in reptiles
6. Cutaneous respiration in insects
7. Skin respiration in mammals

Inside of the animal Kingdomthere are different types of breathing. Cutaneous respiration is one in which gas exchange occurs through the skin or integument of the animal.

To perform cutaneous respiration, animals must have the following features:

1. The skin must be very thin and have a large number of blood vessels, which carry oxygen to the interior of the animal.
2. The skin must be moist. Moisture favors gas exchange and protects the fine skin of the animal.
3. These animals must have low energy requirement. The higher the energy required by the animal, the more oxygen it will need.
4. They should have large surface / volume ratio, that is to say, they must be elongated and thin animals, with a large amount of surface in contact with the environment so that the oxygen input can be the maximum possible.

Image: Mindomo

The vast majority of skin-breathing animals are invertebrates: from earthworms (annelids) to echinorderms (starfish, sea cucumbers, flamingo tongue, sea lily or ophiura).

Large number of invertebrate animals such as annelids They are simple animals, whose habitats are often closely linked to water, so their skin is usually wet and thin. In addition, they are usually small in size so their main mode of gas exchange occurs through the skin.

Secondarily, invertebrates can develop gills in more advanced stages of its life cycle, but the main source of gas exchange is the skin.

Image: Slideshare

Skin respiration not the main breathing system of the fishes. Most gas exchange in fish occurs through gills, but respiration through the cuticle of these animals may represent between 5% and 40% of the total oxygen uptake from the water, depending on the species and the temperature of the medium.

To date, the fish with the highest rate of cutaneous respiration are the jumping fish or coral fish, in which oxygen uptake through the skin represents 50% of total respiration.

Although some species of amphibians depend solely on skin respiration to survive, the vast majority rely on lung respiration or gill, especially when they reach their adult stage.

When the toads They are out of the water, the mucous glands in the skin continue to moisten it, which allows a process of absorption of oxygen from the air to take place. Therefore, its main respiratory system continues to be skin respiration. In some species, such as lungless salamanders or tlaconets, the respiration is given exclusively by the skin because they lack lungs.

The reptileshave, in general, a hard skin full of scales, which make it very inefficient for breathing. There is the possibility of carrying out a gaseous exchange between the scales or areas where the density of scales is smaller as in the cloaca, but in general cutaneous respiration takes place in reptiles marine.

In some cases, the oxygen intake of marine reptiles can be as high as 30% of the total oxygen required. Some examples of skin-breathing animals within reptiles are the dotted head turtle (Sternotherus minor) wave yellow sea snake (Hydrophis platurus).

Image: Comparative Anatomy

Most insects pick up the oxygen they need to live through a tube or trachea system, since their skin is covered with a hard substance called chitin. This trachea system conducts air into the insect's body, in the same way as the airways of our respiratory system.

However, there are some groups of aquatic and endoparasitic insects in which skin respiration is vital, as your tracheal system cannot supply the necessary oxygen on its own. For example, the dithiscids (Dytiscidae), which take the air out of the water with the end of the abdomen and store it under the elytra (forewings).

As you well know, the breath of the mammals It is not mainly caused by the skin but through the lungs. Mammals are too large animals, with too many energy demands and too little surface area to have skin respiration. In addition, we have a thick and waterproof skin, which prevents massive water loss but also effective skin respiration.

You will be surprised to know that, despite being ineffective, Humans do have a small percentage of skin respiration. A human being can take on average between 1% and 2% oxygen from the air, this does not allow us to take all the oxygen that we need to sustain ourselves, but it does allow us to perform other necessary secondary functions What perspiration, that allows us to lower our body temperature when we are hot.

Another curious example of skin-breathing animals are the bats. These animals are able to capture around the 12% oxygen they need through the membranes of their wings, since they are formed by a thin layer of skin, highly vascular.

If you want to read more articles similar to Skin-breathing animals, we recommend that you enter our category of biology.

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