When we go to the beach and we saw a color black marine animal we immediately swim as fast as we could right? This marine animal is called sea urchin. All of us are familiar with sea urchin and probably, most of us feel scared when we see this marine animal.
They don’t have eyes and nose to sense but they are sensitive to touch light and chemicals. What are those spies used for? Their spies used as a function of their eyes, and for protection also. They use their spies if there’s an enemy as well as to sense danger.
Sea urchins can be found on the seafloor. You can found sea urchins mostly on the rocky area. They have a long body shape and long spies on it. They used their spies for protection and also to trap their foods. The feet of sea urchins are all spies and they used it to trap food from the sea floor, walking and also to hold the ocean floor. They used also their spies to suck water from the ocean.
Does sea urchins have a mouth also? Well, definitely yes. Sea urchin's mouth can be found at the center of their body. It has a 5 tooth-like plate and they used it for feeding. They also have the anus and it is located in the upper part of their body. Does sea urchins also have a brain? They do not have a brain just like algae and other echinoderms. They only have water- vascular system that helps them to move and eat their food.
There are around 200 different species. Some of them are rocky and hard in shells while others are soft and chalky plate. Sea urchins eat both plant and animals because they are considered as omnivores. They usually eat algae, rocks, fish and other animals that already decomposed.
Sea urchins don’t have a penis, unlike the human. Their reproduction is done at the water. The male sea urchins can detect if the female sea urchin is ready for production. Two species of sea urchins from the icy waters of Antarctica protect their young from the harsh conditions outside their bodies for several months before 'giving birth', according to biologists in France.
The young develop in womb-like pouches inside the test, or shell, of the female urchin until they are about four millimeters long and fully armed with spines. Other species of sea urchins simply release millions of gametes into the water, and the resulting larvae must fend for themselves. When the baby sea urchins come out they immediately hold at the spies of their mother, it serves as their protection.
Sea urchins are one of the unique marine animals in the world that’s why we need to protect and preserve them. They have a unique behavior, sense organs, digestion, circulation, and even reproduction. What makes them more unique are their spies, that serves as their eyes, senses and also for protection. Sea urchins also serve as a tourist attraction and even to earn money.
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