The kidneys are compound tubular concerned with excretion of urine. It consists of excretory or uriniferous tubules, which produce urine, conducting tubules, which convey urine form the kidney to the renal pelvis, and blood vessels. The kidneys are embedded in fat and each kidney is covered by a capsule of dense collagenous fibres and a […]
The urinary system consists of the glandular organs, the kidneys and the excretory passages, the ureter, the urinary bladder and the urethra. Kidneys Histology of nephron Blood supply to kidney Excretion of Urine Species difference in Kidney Renal Pelvis and calyces Ureter Blood vessels Urethra will be discussed in ‘Histology of Reproductive System’.
Pancreas is a dual gland, which consists of an exocrine portion that secretes certain digestive juices and endocrine portion that secretes hormones. Both these functions of pancreas are carried out by distinctly different groups of cells. It is compound tubuloalveolar gland. The pancreas is covered by a thin layer of loose connective tissue (which does not form a distinct
Gall bladder is a diverticulum of the hepatic duct developmentally to store bile It is absent in horse, elephant, rat and pigeon. Duct of gall bladder is called cystic duct, which unites with hepatic duct and forms the bile duct. Structure Similar to large bile ducts. The wall consists of the following layers. Mucosa consisting of a
The liver is the largest gland in the body and is an important metabolic organ of many functions. It has also an exocrine function, the secretion of bile, which is conveyed to the intestine by a system of ducts. The organ is invested with a connective tissue sheath called the Glisson’s capsule most of which is covered
Lymph capillaries begin as blind tubules in the lamina propria in the stomach and as the lacteal in the small intestine, which occupies the center of the long axis of each villus. These small lymph capillaries form a plexus in deeper part of the lamina propria, from which large vessels arises. Pass through the muscularis
The Nerve to stomach and intestine is from the autonomic nervous system and consists of non-medullated sympathetic fibres and medullated preganglionic parasympathetic fibres. They reach the intestinal wall through the mesentery and form a myenteric plexus or plexus of Auerbach in the inter-muscular connective tissue, in association with the ganglion cells of the parasympathetic system. From the plexus, fine
The arteries reach the gastro-intestinal trunk through the mesentery or omentum, gives off small branches to serosa and pass through the muscular coats to submucosa where they form an extensive plexus of large vessels called Heller’s plexus. From this plexus, one set of branches passes outward to supply the muscular coats and another set passes inward
The large Intestine consists of caecum, colon and rectum and the general structure of these parts are similar. The structure of large intestine resembles that of the small intestine except for the following differences. Mucosa There are no villi. Intestinal glands or crypts of Lieberkuhn are present throughout and they are longer and straighter. The
Intestine consists to two parts – small and large. The small intestine is divisible into three portions, – duodenum, jejunum and ileum, which gradually pass into one another. Their general structure is similar although each division has certain distinctive features. The intestinal wall consists of a mucosa, submucosa, muscularis and a serosa. Tunica mucosa This may be divided into the following layers: Epithelium Lamina
