Rafa koralowa

'Sea in Sight'

The Coral Reef

A coral reef is an accumulation of dead and living skeletons of reef-producing, plant and animal organisms. They include, among others, colonial corals, annelids and molluscs. Coral reefs are formed in seas and oceans in which the water temperature is above 18 ° C and the depth reaches 50 m. They are most often located near the coast in the continental shelf zone, but they can also be lonely, for example in the shape of an atoll. The salinity of the water must be between 27 ‰ and 40 ‰ and it should be in motion for food to reach the organisms. Life thrives on the outermost parts of the reef.

Anemones live in almost all the world's seas. We include them as corals. They are sedentary creatures, but they can move slowly, and they are characterized by the antennae and the foot. Anemones are stingrays that have the form of single polyps that do not form a skeleton. They have the ability to incapacitate larger animals, such as fish.

489 species of sharks are known. Sharks are found mainly in tropical and subtropical seas. The smallest sharks are 15 cm long and the largest 10 meters long. The most dangerous species are: great white shark, tiger shark and bull shark.

The man-eater shark is the only shark that sticks its head above the surface of the water while hunting its prey. People began to consider sharks to be the most dangerous animals to humans after the Jaws movie series. Sharks can replace 35,000 teeth in their lifetime.

Shrimp are marine and freshwater crustaceans. There are over 2,500 species of shrimp and they are found in waters all over the world. Their body is flattened back-ventral and they have poorly developed pincers. The heart of the shrimp is in the head. The Tiger Shrimp is the largest shrimp gautnek. Shrimps live from 1 to 1.5 years. A female shrimp can lay one million eggs at a time, and the hatching period is two weeks.

The hidden weapon of shrimps.

Jellyfish is one of the morphological forms of jellyfish with a gelatinous body, usually bell-shaped or umbrella-shaped, and is essentially sexually reproducing. Jellyfish are predatory. They use stingers to catch their prey and to defend themselves. The second life form of stingrays is the polyp.
The body of the jellyfish shows radial symmetry. It has the shape of a more or less flattened umbrella, bell, disk or mushroom. It consists of the outer epidermis and the inner gastroderm. In the epidermis there are epithelial-muscular and stinging cells. Jellyfish cannot control movement. They are dependent on the movements of water, wind and other external stimuli. They cannot escape predators. In order to protect them, they produce venom in the stinging cells. When its stinging stick comes into contact with another object, the venom is released.