Essential Anatomy and Physiology Components

Essential flesh and Physiology ComponentsMahbubul AlamTask 1Most of the nutrients in the feed ar great(p) molecules that keep non be directly absorbed in the gut due to their size or hydrophobicity. The digestive system is accountable for the re channelion in the size of these molecules directly absorbable d profess(p)er units and the conversion of hydrophilic molecules with hydrophobic building complexes. Proper operation of engrossment and transport mechanisms is essential for the deli rattling of products of digestion in human body cells . An abnormality of one of these systems can exploit malnutrition even in the presence of sufficient nutrition .Functions of Digestive formThe task of the digestive system is the fleshly and chemical breakdown of forage. In addition, energy needed by the body , as well as raw materials for growth and invigorate of body structures come from the viands and drink that ingerimos. In the digestion process be the following functions T est food through the senses of smell and taste, food crushing , dissolution in body of water, food transport crushed decay of food into simple substances with the aid of digestive enzymes, absorption simple substances, and elimination of indigestible residues.Regulation of digestive functionsDigestive functions traction and secretion atomic number 18 controlled by cardinal main types of command the nervous regulation and hormonal regulation .Neural MechanismsNervous regulation of motor and secretory phenomena uses deuce types of neural networks a local system , the enteric nervous system and the autonomic nervous system (ANS ). Nerve receptors are sensitive to various stimuli the chemical composition of the chime(acidity) , stretching (feeling of fullness ) , etc. . They send impulses to the heft and secretory cells of the digestive tract via the enteric nervous system consists of the myenteric plexus and submucosal . Neurotransmission is nervous or chemical type ( enkephali ns , somatostatin , serotonin, bombesin , neurotensin , etc. . ) .The ANS consists of two contingents of fibers sympathetic fibers that run along roue vessels, and the parasympathetic fibers of the tenth cranial nerve nerve. These two contingents have antagonistic actions roughly, sympathetic fibers are inhibitory while the parasympathetic fibers are excitatory .StructureCore Structures Mouth, pharynx , esophagus , hold thin gut , AnoAssociated structures salivary secretory organs ( three pairs ) , Pancreas , Liver, vex Bladder ( with their associated ducts) , and Appendix.ProcessThe substances that the body needs are absorbed from food , it passes through the digestive system. When chewing food, it is moistened by saliva. As food is sufficiently fragmented and wet rima oris are pushed by the expectoration into the pharynx and swallowed. The muscles in the walls of the esophagus contract and relax to cause movement in waves, known as peristalsis, which lowers food into the jut out. In this , mixed with acidic juices produced by the wall of the organ. These juices facilitate the fragmentation of food in even small-scaleer particles , the muscles of the stomach wall also contract , and facilitating the greater fragmentation.Thereafter , they pass into the small gut where certain products contained in the digestive juices , known enzymes continue the degradation of food in nutritionary components which are absorbed by the blood through the walls of the small intestine. Leftover food particles , which are not digested in the small intestine pass into the large intestine where water is absorbed. The remaining food is a partially solid waste is gradually propelled along the large intestine and takes the form of feces come across the rectum. The depositions are stored in the terminal portion of the digestive tract and are then expelled through the anus.AnatomyThe esophagus is a tube or membranous muscle that extends from the pharynx to the stomach. Incisors to cardia ( portion continues where the esophagus and stomach) there are about 40 cm. Esophagus begins at the neck, chest and traverses into the abdomen through the esophageal curtain raising diaphragm . Usually it is a virtual cavity ( ie that its walls are joined and only airfoil when the bolus passes ) . Measure reaches the esophagus 25 cm and has a structure consisting of two layers of muscles which allow contraction and residue of the esophagus downward . These waves are called peristalsis and is causing the progress of food into the stomach. Its just a rush of the bolus , and is the union of different holes , oral , nasal , ear and larynx.StomachThe stomach is an organ so that varies depending on the state of repletion (amount of nutritional content present in the gastric cavity) that is usually shaped J. It consists of virtually(prenominal) parts that are fundus, body, antrum and pylorus. Its less extensive edge is called the lesser curvature and a larger cur vature. The cardia is the margin in the midst of the esophagus and stomach and pylorus is the boundary between the stomach and duodenum. In an individual measures approximately 25cm cardia to the pylorus and the thwartwise diameter is 12cm. To see what is inside the stomach click here.Small intestineThe small intestine begins at the pylorus and ends at the ileoceal valve, which is attached to the first part of the large intestine. Its length is variable and its size gradually decreases from its transmission line to the ileocecal valve. The duodenum, which is part of the small intestine, is about 25 to 30 cm in length, the small intestine consists of a proximal portion and a distal jejunum or the ileum, the boundary between the two portions is not very apparent. The duodenum joins the jejunum after 30cm from the pylorus. The jejunum-ileum is part of the small intestine that is characterized by relatively fixed ends The first originates in the duodenum and the gage is limited to the ileocecal valve and first portion of the blind. Its size decreases slowly but progressively towards the large intestine. The boundary between the jejunum and ileum is not noticeable. The small intestine villi has numerous surface increasing intestinal absorption of nutrients.IntestineThe large intestine . starts from the ileocecal valve in a blind pouch called from where the vermiform appendix and ends at the rectum . From the cecum to the rectum describes a series of curves , forming a frame in the center of the handles are yeyunoleon . Its length is variable between great hundred and 160 cm , and its size gradually reduces , being narrower in the region where it joins portion rectum or recto sigmoid junction, where the diameter is usually not exceed 3 cm , while the blind is 6 or 7 cm.After the blind , the second portion of the large intestine is called as ascending colon, with a length of 15cm , to give rise to the third portion which is the transverse colon with an average length of 50 cm , resulting in a fourth portion which is the descending colon 10cm in length. Finally differs sigmoid , colon rectum and anus . The rectum is the last part of the digestive tract. It is the continuation of the sigmoid colon and ends up opening up to the outside through the anal opening .PancreasGland is intimately cerebrate to the duodenum, the excretory duct of the pancreas, which ends agree with the gall through the ampulla of Vater, their secretions areimportant in the digestion of food .LiverThe liver is the largest internal organ of the body weighs 1500 grams. It consists of two lobes. The bile ducts are the excretory ducts of the liver , bile for them is driven into the duodenum . normally get two transmit left and right , that converge together to form a single duct . the hepatic duct receives a finer duct, cystic duct coming from the gall bladder housed in the visceral side of liver. run across of the cystic duct and the hepatic bile duct , descending d uodenum , into which together with the excretory duct of the pancreas is formed. The gallbladder is a reservoir musculomembranous shunted on the main bile duct. It contains about 50-60 cm3 of bile. Is oval or slightly circular , and its major diameter is about 8 to 10 cm .SpleenThe spleen , for its main functions should be considered an organ of the circulatory system. Its size depends on the amount of blood contained therein.Digestive PhysiologyThe gastrointestinal tract is responsible for the digestion of the ingested food , so that they can be used by the body . The process of digestion begins in the mouth where food is covered by saliva , crushed and divided by the action of chewing and once formed the bolus swallowed . The stomach is not an essential organ for life, for though his removal in man and animals cause certain digestive disorders, not fundamentally affect health.In humans , the essential function of the stomach to reduce food to a semi-fluid mass of uniform consist ency called chyme , which then passes into the duodenum . The stomach also acts as a temporary reservoir for the acid foods and their secretions , has some antibacterial action.The chyme passes the pylorus and enters the duodenum intervals where it is transformed by the secretions of the pancreas , small intestine and liver was continued digestion and absorption. Chyme is progressing through the small intestine until it reaches the large intestine.The ileocecal valve too fast hinders the emptying of the small intestine and prevents reflux of the contents of the large intestine to the small intestine. The main function of the large intestine is the institution , transport and disposal of feces. A very important function is to absorb water. In the cecum and ascending colon faeces are al more or less liquid and that is where the greatest amount of water and some dissolved substances are absorbed, but also in more distal regions ( rectum and sigmoid colon) liquids are absorbed.Digestio n and absorptionDigestion of food is effected by hydrolysis using digestive enzymes and cofactors much(prenominal) as hydrochloric acid or bile . Cofactors are also involved in the mechanisms of absorption. Enzymes are of 2 types exoenzymes and endoenzymes.Digestive enzymes are exoenzymes mainly synthesized by specialized cells of the mouth, stomach , pancreas or small intestine and that are released in the digestive light to turn the hydrolysis of the food to the outside of the cell .The enzymes are endoenzymes localized on the membrane lipoproteins digestive mucosal cells . The club to their substrate therefore when those latter penetrate into the cell. Ingested food are absorbed about 95%. The water , inorganic salts , monosaccharides , vitamins and alcohol are absorbed without change. As against , disaccharides , polysaccharides , lipids and proteins are to be transformed by hydrolysis into simpler components out front being absorbed.Factors influencing the digestionPsycholo gical factorsThe appearance, smell and taste of food served modifies the emotional climate during the meal which influences the digestion of ingested food. Indeed , salivary secretions , gastric , etc. . and variegate motility of the digestive tract . Emotions such as fear , misgiving or anxiety act via the hypothalamus and the autonomic nervous system affect digestion by reducing secretions , quelling of peristalsis and increased sphincter tone .Bacterial action .The intestinal flora is a complex community with over 100 different species.At birth, the gastrointestinal tract is sterile, but many a(prenominal) species cursorily colonize the digestive tract.Lactobacillus is the main bacteria flora until the child gets a varied diet . whence Escherichia coli dominant in the terminal ileum , and the anaerobic flora in the colon appears . However, the number of lactobacilli persist in subjects taking a normal diet.In the stomach , hydrochloric acid (HCl ) has a bactericidal action , which destroys most bacteria in the gastric acid chyme . In hyposcrtion gastric cases, bacterial overgrowth can be responsible for gastritis resulting in inflammation of the mucosa.In the colon , bacterial action is more intense. It leads to the formation of gas (H2 , CO2 , CH4 , O2, NH3 , etc . ) , Acids ( lactic , acetic , etc . ) , And many other substances ( indoles , phenols , etc. . ) . The smell of feces is related to many of these components.The meal ingestion alters the fecal flora in very different ways depending on the individual . The ingestion of carbohydrate fermentation tends to increase while the increase of protein putrefaction .Effects of food preparation and meal composition .Cooking makes them more easily digestible cooking meat relaxes conjugation tissue, facilitates chewing making it more accessible to digestive juices tissues.A heat load and composition compeer meals low volume and more can be better digested than lavish meals .The chemical reactions during cooking alter food digestion . Acrolein produced by frying foods at elevated temperature, delays gastric emptying . Instead, meat get out ( bouillon ) charge digestion .Finally, there is a wide variation within and between individual sensitivity to food, their physical properties (temperature , acidity, etc. . ) That is frequently associated with the state of repletion of the digestive tract .Task 2The Endocrine System and Its WorkingThe hormone system is a term for all the organs and tissues that produce hormones. They are distributed passim the body and can show effects over long distances onGrowthDevelopmentFunctions of many organsCoordination of metabolic processesThe endocrine glands are organs, but who have no ducts, because they distribute their products directly into the blood or an autocrine or paracrine effect, however. Therefore, there is at this tissue with a dense network of blood capillaries with windowed endothelium. exocrine gland gland secretions free to oppos e it with their inner or outer surfaces on the skin, on the wall of the stomach or in the pancreatic ducts. The hormone-producing tissue can be divided into three groupsPurely endocrine glands, used exclusively for the production of hormonesExo-endocrine glands, in addition to the hormones produced other exocrine secretionsCertain non-glandular tissue such as the autonomic nerves, which also secrete hormone-like substances =neuro secretionLocation and Function of 3 Endocrine Glandsthyroid glandDevelopmentally, the thyroid gland goes out of the intestinal epithelium of the pharynx bottom out on the diction base. This gland contributes at the beginning of the development through the ducts thyroglossus still with the floor of the mouth in crew and is located in front of the trachea after a descent. Anatomically, the thyroid gland is composed of two lobes, which are on an isthmus that is sometimes formed as a real pyramidal lobe, in conjunction. Without thyroid hormones cannot live. The thyroid hormonetriiodothyronine (T3) and thyroxin (T4) are iodized. They work in almost all body cells and stimulate there on the energy metabolism. The thyroid itself is in terms of a control system by the hypothalamic hormone TRH (TSH-releasing hormone), and originating from the pituitary TSH (thyroid-stimulating hormone) in their function regulated (Hiller-Sturmhofel, 1998).Endocrine PancreasThe pancreas is an exo-endocrine organ by both digestive juices into the duodenum and releases hormones into the bloodstream. The endocrine portion, the islets of Langerhans are localized mainly in the pancreatic and stand out due to their brighter appearance. They secrete their secretions directly into the bloodstream. A distinction is to effect different types of cellsB cells 60-80%, are used to produce insulinA cells approximately 20%, and are therefore intended to antagonist to insulinD cells about 2% serve to have an inhibitory effect on the A-and B-cells as well as on the exocrine p ancreas.PP cells (pancreatic polypeptide) 1-2% and inhibit pancreatic exocrineThese islands consist of a net-like organization of several k epithelial cells arranged in groups and are crossed by numerous capillaries with windowed endothelium (Carter, n.d.)PituitaryThe pituitary gland is located at the underside of the brain and is composed of three parts. In contrast, the anterior pituitary produces own hormones. The activity of its cells is determined by complex humeral and neural mechanisms regulated (= control hormones). It is above all the hypothalamic releasing and release-inhibiting hormones that play an important role (Drake, 2010)