The digestive system of reptiles has its own characteristics, which make it much more complicated compared to the same structure in amphibians.
General characteristics of reptiles
Reptiles animals got their name due to the nature of movement on the earth's surface. They are either deprived or have short limbs that are located in the horizontal plane. Therefore, they kind of "creep" on the ground. All of them are cold-blooded animals that have mastered both aquatic and terrestrial habitats. But the development of their embryos, which are surrounded by protective egg shells, occurs exclusively on land. The body of reptiles is covered with dry keratinized scales.
The main features of the internal structure are the appearance of a real chest, exclusively pulmonary breathing, internal fertilization and the excretory system of reptiles, represented by the kidneys, bladder and cesspool.
Digestive system: main departments
The digestive system of reptiles is represented by the tract and specialized glands. Unlike amphibians, these animals have salivary glands that produce enzymes. These substances are natural biological catalysts. They break down complex organic substances into simple ones. It is in this form that they are able to be absorbed and stored in reserve. The structure of the digestive system of reptiles is also characterized by the presence of undifferentiated teeth and the cecum. These are the main features of complication in comparison with amphibians.
The digestive tract of reptiles is represented by the oral cavity, pharynx, narrow esophagus, stomach and intestines. The latter is differentiated and consists of thin and thick sections passing into the cecum. The digestive tube ends with a cesspool. This is a hole through which not only undigested food residues are released, but also the products of excretory and reproductive systems.
Digestive glands
The digestive system of reptiles is quite complicated. Digestion of both plant and animal food that they consume would not have been possible without the presence of glands. In addition to salivary matter, the substances and enzymes of which break down, moisturize and facilitate the ingestion of food, reptiles have a liver and pancreas. Each organ performs its function. The liver secretes bile, which disinfects and breaks down food particles. And the pancreas secretes enzymes that complete the breakdown of proteins, fats and carbohydrates.
Enzyme digestive glands enzymes are chemically active substances. So, everyone knows the fact that snakes do not chew food, but capture their entire prey. The process of digestion begins only in the stomach. Sometimes its duration reaches several weeks.
Complications
As already mentioned, the excretory system of reptiles is characterized by certain features of complication. Despite the fact that all the teeth in the oropharyngeal cavity are the same and serve only to capture and hold the extraction, there are also specialized ones. For example, in poisonous snakes. Many believe that they paralyze their prey with the help of the tongue. But this is not at all true. In their oral cavity is a poisonous tooth, in which there is a channel with a toxic substance. And from the mouth of predators, such as crocodiles, it is completely impossible to escape, since their teeth are especially powerful and sharp. For example, the incisors of this animal "work" so often that they change up to several tens of times a year. By the way, unlike amphibians, in many of which the tongue is the organ of food capture, this crocodid organ practically grows together with the base of their oral cavity, therefore it seems that it does not exist at all.
The functions of the digestive system of reptiles
The digestive system is designed to break down and absorb nutrients. When they are split, a certain amount of energy is released, which is used by living organisms to carry out all the processes of life. In this case, the splitting occurs with the help of enzymes of specialized glands, and the movement of food particles from the oral cavity to the cloaca is carried out by the muscle walls of the tract.
So, the digestive system of reptiles has both typical structural features of chordates and some distinctive ones. Obviously, compared to amphibians, it is much more complicated. This is manifested in the presence of digestive enzymes, which are secreted by specialized glands, the cecum and differentiated intestines.