The major abnormalities are altered gastrointestinal motility, disrupted gut barrier function with increased intestinal permeability and malabsorption. The liver turns the toxic ammonia into a substance called urea.
The liver releases this into the blood where the kidneys excrete it via the urine. The liver also removes alcohol from the blood, as well as affects many medications a person takes. The major organs involved in the process of digestion in frogs include mouth, pharynx, esophagus, stomach, small intestine, large intestine, and cloaca. Accessory organs such as the liver, pancreas, and gallbladder are also an important part of the digestive system of frogs. We both have 2 lungs used for breathing.
We both have a mouth, esophagus, stomach, pancreas, liver, gall bladder, small intestine, and large intestine. The teeth are used to hold prey in place until the frog can swallow it.
It is also sometimes called the strawberry dart frog. Color the pancreas yellow. The coils of the small intestine are held together by a thin membrane called the mesentery. Frog lacks salivary glands. Teeth: The lower jaw lacks teeth. However, teeth occur in a row of either side on the premaxillae and maxillae bones of the upper jaw. The teeth are backwardly pointed. Vomers two small bones in the roof of the mouth also consists of two groups of vomerine teeth. The function of teeth is to simply hold the prey and prevent it from slipping out.
Teeth are not meant for chewing. The nature of teeth is homodont similar , acrodont not set in a socket. But teeth are attached to the jaw bone by a broad base made of a bone-like substance. The crown is the free part of tooth. It is made up of dentine a hard ivory-like substance , which is traversed by numerous fine canals or canaliculi.
Enamel covers the tip of the crown. Enamel is a very hard, resistant and glistening substance. Tooth contains a central pulp cavity open at the side. It is filled with a soft nourishing pulp, containing connective tissues, blood vessels, nerve and odontoblast cells that produces new material for the growth of tooth.
Frog are polyphyodont in nature, i. Tongue: In frogs, tongue is large, muscular, sticky and protrusible. It lies on the floor of mouth cavity. The anterior end of tongue is attached to the inner border of lower jaw. The posterior end is free and bifid. This free end can be flicked out and retracted immediately after catching the prey.
The slimy surface of tongue facilitates in capturing the prey. The change of pressure in large sublingual lymph sac causes the protrusion of tongue. Internal nostrils: Just in front of vomerine teeth, the roof of buccal cavity contains anteriorly, a pair of small openings of internal nares. By these internal nares, the nasal cavities open into buccal cavity. These serves in respiration. Bulging of orbits: The roof of buccal cavity shows two large oval and somewhat pale areas, behind the vomerine teeth.
These areas are the bulging of eye balls. In course of swallowing the food, frog depresses the eyes. This causes the orbits to bulge inwards which in response pushes the food towards the pharynx. In the interior of each tooth there is a cavity which is called pulp cavity.
It is filled with a highly vascular and nutritive tissue or pulp which also contains odontoblast cells which produce new material for the growth of teeth. During lifetime the old and worn out teeth are being continuously replaced by new ones which are produced below the old ones which are cast out or lost. As the teeth are replaced several times during the lifetime of the frog, so they are called polyphyodont.
The buccal cavity in its roof near the vomerine teeth has two openings, the internal or posterior nares connecting with the nasal cavities through which the respiratory gases pass to and from the buccal cavity during respiration.
The large, thick, fleshy and protrusible tongue attached in front to the inner border of lower jaw, and free and notched behind lies on the floor of the buccal cavity. Its upper surface bears taste buds in the form of small papillae and mucous glands of which the secretions make the tongue sticky. Neither taste buds nor mucous glands produce any digestive enzymes. The tongue can be thrown out and retracted suddenly to capture and engulf insects.
According to Hartog, the throwing out of the tongue is brought about by the sudden flowing of squeezed lymph from the lymph sac to another due to muscular contraction but the swallowing is accomplished simply by raising the floor of the buccal cavity in which a flat hyoid cartilage is embedded. The roof of buccal cavity behind the vomerine teeth has two large, oval pale areas, the bulgings of eyeballs. During swallowing of food, eyes are depressed into the buccal cavity which pushes the food into the pharynx.
The buccal cavity narrows behind as the pharynx which in turn opens into the oesophagus through gullet. In the roof of the pharynx on either lateral side is present a wide eustachean opening which communicates with the middle ear. The glottis which is a median slit in the pharynx behind the tongue guards the entrance to the lungs. It is always opened during breathing but closes while food is being swallowed. In male frog two openings of vocal sacs are also formed in the angle of the lower jaw on the floor of the pharynx.
These act as resonators at the time of croaking. The gullet leads into a short, broad and muscular part of the alimentary canal called oesophagus. This part of the alimentary canal is very short due to the absence of neck but highly distensible as its inner lining is thrown into a large number of longitudinal folds which allow the sufficient expansion of the oesophagus during the passage of the ingested food through it to the stomach.
It opens into the stomach in such a way that no demarcation line is formed between the oesophagus and stomach. It is the most important part of the alimentary canal where the digestion of ingested food takes place with the help of certain digestive enzymes secreted by the digestive glands situated in its wall.
It is in the form of wide and curved tube and lies between the oesophagus and intestine. It is suspended by a mesentery, the mesogaster, into the left side of the body cavity or the coelom. It is distinguished into two parts — the large wider anterior cardiac stomach and the posterior, short narrow pyloric stomach.
The internal lining of the stomach has numerous longitudinal folds which may allow the expansion of the stomach whenever needed. Its mucous epithelium possesses multicellular gastric glands which secrete pepsinogen enzyme, and unicellular oxyntic glands which secrete hydrochloric acid. The pyloric end of stomach is constricted and its opening into small intestine is guarded by sphincter a circular ring-like muscle. It regulates the passage of food from the stomach into the intestine.
The stomach leads into the long, tubular and coiled intestine. It is also attached to the dorsal body wall by mesentery. The small intestine lies in several loops supported by a fan-like membrane, the mesentery. The anterior region of the small intestine which curves upwards to form a U with the stomach is the duodenum, the rest part of it continues as the coiled ileum. In the duodenum opens a common hepato pancreatic duct from liver and pancreas bringing the bile and pancreatic juice.
The internal mucous lining is thrown into low transverse folds. The ileum is a long, narrow, very much coild tube and its lower end leads into rectum large intestine. The internal mucous lining of ileum forms a number of longitudinal folds. True villi, glands and crypts of higher vertebrates are absent.
Digestion and absorption of food takes place in this part. Its lower end opens into cloaca by spinctered anus. Its mucosal lining forms low longitudinal folds. It is a small sac-like structure and receives the openings of anus and urinogenital apertures. Cloaca opens towards the exterior through vent or cloacal spening situated at the posterior end of the body. Two large digestive glands, in addition to the glands located in the stomach and small intestine, are also found in the frog.
These glands are the liver and the pancreas. It is the largest reddish brown gland found in the anterior region of the body cavity close to the heart and lungs. It consists of two lobes-the right and the left. These two lobes remain connected with each other by a narrow bridge of liver tissue.
The left lobe is again subdivided into two lobes. Between the right and left lobes, a thin-walled, round, large, greenish sac, the gall bladder, is found. It serves as a reservoir for the bile constantly secreted by the liver cells.
The bile passes into the gall bladder through cystic ducts as well as directly into the bile duct by way of minute hepatic ducts. The hepatic and crystic ducts join to form a common bile duct which runs through the pancreas and opens into the duodenum. The common bile duct is also known as hepatopancreatic duct as it receives the fine ducts of the pancreas on its way to the duodenum. Bile lacks digestive juices. Bile only emulsifies fats, thus, liver is not a true digestive gland. The liver is composed of numerous lobules or tubules which not only branch but also anastomose with another to form a complex network due to which it is sometimes called as a reticular gland.
These lobules are separated from each other by the presence of connective tissue containing bile capillaries, hepatic ducts, blood sinuses and blood capillaries. Each lobule is made up of numerous polyhedral, glandular hepatic cells which contain nuclei and cytoplasm along with protein granules, droplets of fats, glycogen and often black or dark brown pigment granules.
The hepatic cells are arranged in columns between the bile capillaries which invite to form larger hepatic ducts. Hepatic ducts ultimately open into cystic duct directly attached with the gall bladder. The hepatic ducts of different lobes and cystic duct unite to form the bile duct. The liver receives blood from the hepatic artery and the hepatic portal vein. These blood vessels enter the liver and provide the required material for the formation of bile.
And, their chest muscles are not used for breathing. They also serve as a food source for many larger wildlife species. Also, frogs have been essential to several medical advances that help humans. New painkillers and antibiotics have been created due to research on the substances they secrete through their skin. The liver is the only solid internal organ capable of full regeneration.
This means the remaining portion of your liver will grow back after surgery. As little as 30 percent of your liver can regrow to its original volume. Most people feel it as a dull, throbbing sensation in the upper right abdomen. Liver pain can also feel like a stabbing sensation that takes your breath away. Sometimes this pain is accompanied by swelling, and occasionally people feel radiating liver pain in their back or in their right shoulder blade.
If the stools are pale, it may indicate a problem with the liver or other part of the biliary drainage system. Black tarry stools can happen in advanced liver disease and are caused by blood passing through the gastrointestinal tract — this needs urgent medical attention. Several disorders of the liver and gallbladder can impair the action of bile, preventing the proper breakdown of fats in the intestine.
For example, this can occur in people with gallstones or liver cirrhosis. Bile acid malabsorption can cause diarrhea or loose stools.
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