We can see many animals in every part of the world. We are familiar with some of these animals but others are not. We are not really familiar with other animals especially the marine animals. We seldom touch them nor seeing them especially the sea cucumbers. What are sea cucumbers?
Sea cucumbers are found on the sea floor worldwide. Sea cucumbers are echinoderms—like starfish and sea urchins. We can see a lot of them when we are having our scuba diving. Some of us are afraid to them that others treat them as food and they are not afraid of it. They don’t have feet and hand, just like what humans have and these questions triggered our mind. Are sea cucumbers a living being? How can they breathe if they’re human being?
The most surprising part there is to know that sea cucumbers are living being. Yes! Definitely, they are animals and they are not plants. They are marine animals with a leathery skin and elongated body. They also have body parts that enable them to survive. They have a unique body plan which can make other people amazed. Their body wall consists of an epidermis and a dermis and contains smaller calcareous ossicles, the types of which are characteristics which help to identify different species.
Other animals have esophagus to carry food from mouth to stomach but sea cucumbers don't have and that what makes them more unique. They only have a pharynx that opens directly into the intestine. Does a sea cucumber have a brain? No, they don’t have a true brain. A ring of neural tissue is the only thing that sends nerves to the tentacles and pharynx. When the nerve is removed they can still move their body and enable to function every essential part of it because they don’t have a central role that controls their nervous coordination. These what makes sea cucumber a living being, Amazing! Isn’t it?
Sea cucumbers are living being so, probably they can breathe. How do they breathe? They can breathe using their anus. Yes, you read that right. Sea cucumbers breathe through a respiratory tree that is connected to their anus. The sea cucumbers breathe through oxygenated water by the use of their anus.
Together with the intestine, the respiratory trees also act as excretory organs, with nitrogenous waste diffusing across the tubule walls in the form of ammonia and phagocytic coelomocytes depositing particulate waste. That makes their anus most essential part of their body and they can be able to live through it.
Now, we already know what sea cucumber is. Let’s try to protect them because they are also a living being. Though they can’t feel just like what we feel still they are living being. They’re the shelter of some animals. They can greatly help in cleaning the sea floor. Although they’re higher in number we still need to protect and preserve the sea cucumber.