Venus bhatnagar science institute

Bile duck Bile, required for the digestion of food, is secreted by the liver into passages that carry bile toward the hepatic duct, which joins with the cystic duct (carrying bile to and from the gallbladder) to form the common bile duct, which opens into the intestine. The biliary tree (see below) is the whole network of various sized ducts branching through the liver. The path is as follows: Bile canaliculi → Canals of Hering → interlobular bile ducts → intrahepatic bile ducts → left and right hepatic ducts merge to form → common hepatic duct exits liver and joins → cystic duct (from gall bladder) forming → common bile duct → joins with pancreatic duct → forming ampulla of Vater → enters duodenum. Structure Bile duct is green like the gallbladder, because of bile stains Innervation Inflation of a balloon in the bile duct causes, through the vagus nerve, activation of the brain stem and the insular cortex, prefrontal cortex, and somatosensory cortex. Clinical relevance Blockage of the...

Small intestine The small intestine (or small bowel) is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. The small intestine is composed of a duodenum, jejunum, and ileum. It receives bile juice and pancreatic juice through the hepatopancreatic duct, controlled by the sphincter of Oddi. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to describe the entire intestine. This article is primarily about the human gut, though the information about its processes is directly applicable to most placental mammals. The primary function of the small intestine is the absorption of nutrients and minerals found in food. (A major exception to this is cows; for information about digestion in cows and other similar mammals, see ruminants and platypus.) Structure The average length of the small intestine in an a...

Pancreas The pancreas is a glandular organ in the digestive system and endocrine system of vertebrates. In humans it is located in the abdominal cavity behind the stomach. It is an endocrine gland producing several important hormones, including insulin, glucagon, somatostatin, and pancreatic polypeptide which circulate in the blood. The pancreas is also a digestive organ, secreting pancreatic juice containing digestive enzymes that assist digestion and absorption of nutrients in the small intestine. These enzymes help to further break down the carbohydrates, proteins, and lipids in the chyme. Structure The pancreas is an endocrine organ that lies in the abdomen, specifically the upper, left abdomen. It is found behind the stomach, with the head of the pancreas surrounded by the duodenum. The pancreas is typically 5.75-9.5 cm long. Anatomically, the pancreas is divided into a head, which rests within the concavity of the duodenum, a body lying behind the base of the stomach, and a tail,...

Thyroid The thyroid gland or simply, the thyroid /ˈθaɪərɔɪd/, in vertebrate anatomy, is one of the largest endocrine glands. The thyroid gland is found in the neck, below the thyroid cartilage (which forms the laryngeal prominence, or "Adam's apple"). The thyroid gland controls how quickly the body uses energy, makes proteins, and controls how sensitive the body is to other hormones. It participates in these processes by producing thyroid hormones, the principal ones being triiodothyronine (T3) and thyroxine (sometimes referred to as tetraiodothyronine (T4)). These hormones regulate the growth and rate of function of many other systems in the body. T3 and T4 are synthesized from iodine and tyrosine. The thyroid also produces calcitonin, which plays a role in calcium homeostasis. Hormonal output from the thyroid is regulated by thyroid-stimulating hormone (TSH) produced by the anterior pituitary, which itself is regulated by thyrotropin-releasing hormone (TRH) produced by ...

Lung The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart. Their principal function is to transport oxygen from the atmosphere into the bloodstream, and to release carbon dioxide from the bloodstream into the atmosphere. A large surface area is needed for this exchange of gases which is accomplished by the mosaic of specialized cells that form millions of tiny, exceptionally thin-walled air sacs called alveoli. To understand the anatomy of the lungs, the passage of air through the nose and mouth to the alveoli must be studied. The progression of air through either the mouth or the nose, travels through the nasopharynx, oropharynx, larynx, and the trachea (windpipe). The air passes down the trachea, which divides into two main bronchi; these branch to the left and right lungs where they progressiv...

Pituitary In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and weighing 0.5 grams (0.018 oz) in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain, and rests in a small, bony cavity (sella turcica) covered by a dural fold (diaphragma sellae). The posterior pituitary (or neurohypophysis) is a lobe of the gland that is functionally connected to the hypothalamus by the median eminence via a small tube called the pituitary stalk (also called the infundibular stalk or the infundibulum). The anterior pituitary (or adenohypophysis) is a lobe of the gland that regulates several physiological processes (including stress, growth, reproduction, and lactation). The pituitary gland sits in the hypophysial fossa, situated in the sphenoid bone in the middle cranial fossa at the base of the brain. The pituitary gland secretes nine hormones that regulate homeostasis. Structure The pituitary gland is a pea-sized ...

Heart The human heart is a vital organ that functions as a pump, providing a continuous circulation of blood through the body, by way of the cardiac cycles. The heart is contained in the mediastinum in the thoracic cavity of the thorax. The heart is enclosed in a protective sac, the pericardium which also contains a lubricating pericardial fluid. The outer wall of the heart is made up of three layers, the epicardium, the myocardium which is the muscle of the heart, and the endocardium. The heart is divided into four main chambers: the two upper chambers are called the left atrium and the right atrium (plural atria) and the two lower chambers are called the right and the left ventricle. There is a dividing wall of muscle, called the septum, which separates the right side of the heart from the left side of the heart. The part of the septum that separates the ventricles, the ventricular septum is thicker than that which separates the atria, the atrial septum. Normally with each heartbeat,...

Stomach The stomach is a muscular, hollow, dilated part of the digestion system which functions as an important organ of the digestive tract in some animals, including vertebrates, echinoderms, insects (mid-gut), and molluscs. It is involved in the second phase of digestion, following mastication (chewing). The stomach is located between the esophagus and the small intestine. It secretes protein-digesting enzymes called proteases and strong acids to aid in food digestion, (sent to it via esophageal peristalsis) through smooth muscular contortions (called segmentation) before sending partially digested food (chyme) to the small intestines. Structure The stomach lies between the esophagus and the duodenum (the first part of the small intestine). It is on the left upper part of the abdominal cavity. The top of the stomach lies against the diaphragm. Lying behind the stomach is the pancreas. The greater omentum hangs down from the greater curvature. Two sphincters keep the contents of the ...

Liver The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion. The liver is necessary for survival; there is currently no way to compensate for the absence of liver function in the long term, although new liver dialysis techniques can be used in the short term. This gland plays a major role in metabolism and has a number of functions in the body, including glycogen storage, decomposition of red blood cells, plasma protein synthesis, hormone production, and detoxification. It lies below the diaphragm in the abdominal-pelvic region of the abdomen. It produces bile, an alkaline compound which aids in digestion via the emulsification of lipids. The liver's highly specialized tissues regulate a wide variety of high-volume biochemical reactions, including the synthesis and breakdown of small and complex molecules, many of which are necess...

Large intestine The large intestine is the last part of the digestive system in vertebrate animals. Its function is to absorb water from the matter, and then to pass useless waste material from the body. Terminologia Anatomica, Medscape, and Gray's Anatomy define the large intestine as the combination of the cecum, colon, rectum, and anal canal. Other sources, such as Mosby's Medical Dictionary and the Oxford Dictionaries of Medicine and Biology exclude the anal canal. In humans, it begins in the right iliac region of the pelvis, just at or below the waist, where it is joined to the end of the small intestine. It then continues up the abdomen, across the width of the abdominal cavity, and then down to its endpoint at the anus. Overall, in humans, the large intestine is about 1.5 metres (4.9 ft) long, which is about one-fifth of the whole length of the intestinal canal. Structure The colon is the last part of the digestive system in most vertebrates. It extracts water and salt f...

Kidney The kidneys are bean-shaped organs that serve several essential regulatory roles in vertebrate animals. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and regulation of blood pressure (via maintaining salt and water balance). They serve the body as a natural filter of the blood, and remove water soluble wastes, which are diverted to the urinary bladder. In producing urine, the kidneys excrete wastes such as urea and ammonium, and they are also responsible for the reabsorption of water, glucose, and amino acids. The kidneys also produce hormones including calcitriol, erythropoietin, and the enzyme renin. Located at the rear of the abdominal cavity in the retroperitoneum, the kidneys receive blood from the paired renal arteries, and drain into the paired renal veins. Each kidney excretes urine into a ureter, itself a paired structure that empties into the urinary bladder. Renal...