In the event that sense represents an important constituent for animals in general, it is considered as a critical element for the life of birds, in particular. Sense is an essential component to a bird for a perfect accommodation of its way of life. An individual gains knowledge of its environment through its sensory organs. A sense organ is that organ through which an animal gains information about its surroundings. The three predominating sense organs in animals are those of smell, sight and hearing.

Marine organisms are a wonderful source of biologically active natural products. Sea cucumbers are among the marine organisms which use as traditional food, especially in Asia. They are cylinder-shaped invertebrates that live in a variety of sea floor habitats from warm tropical waters to cold deep-sea trenches. Holothuria atra is the most important and abundant sea cucumber species in the Red Sea on the Saudi Arabia coast. Sea cucumber contains physiologically active phenolic compounds with antioxidant activity, which afforded a potential therapeutic activity against hepatorenal diseases.

In the event that sense represents an important constituent for animals in general, it is considered as a critical element for the life of birds, in particular. Sense is an essential component to a bird for a perfect accommodation of its way of life. A sense organ is that organ through which an animal gains information about its surroundings. The three predominating sense organs in animals are those of smell, sight and hearing.

The study of the cranial nerves is important because their distribution is correlated to the habits and habitats of animals and also because they show an evolutionary trend among the animals of the same group. The cranial nerves connect the brain with all the important centers of perception of the outer surface of the head, as well as the inner surface of the buccopharyngeal and the other visceral regions, so that they seem to be important in determining the behavior of animals.