Digestive system - Lab Report Example

Human Anatomy Lab Report Topic: Digestive Systems Saliva aids in formation of food boluses in addition to lubricating, protecting, and cleansing the pharyngeal and esophageal mucosa. Enzyme amylase catalyzes breakdown of starch into sugars (trisaccharides and disaccharides); these sugars are later converted to glucose which supply energy to the body in form of ATP.2. Enzyme pepsin helps in degradation of food proteins into peptides. Gastric gland also secretes other substances, such as enzyme rennin that curdles milk.

Hydrochloric acid (HCL) produced by parietal cells activates enzymes that are in inactive form to active form: for instance pepsinogen (inactive form) to pepsin (active form); mucus helps to protect the stomach walls from corrosive effect of HCL.3. Enzyme lactase helps in breakdown of lactose to simple sugars galactose and glucose; it does this by a process called hydrolysation whereby a molecule of water is released. Whole milk contains lactose this was broken down by enzyme lactase to galactose and glucose which led to increase of glucose concentration with time as more glucose was being released.

Lactose-free milk stayed the same because it lacked lactose and lactase enzyme digests lactose only.4. The pancreas is an organ that secretes pancreatic juice, a major digestive secretion. Alkaline pancreatic secretions help in neutralization of the acid chyme (food) from the stomach to a neutral or slightly alkaline pH; this is important because most pancreatic enzymes work best at slightly alkaline or neutral PH, excess acidic PH can also damage duodenal mucosa and cause ulcers. Pancreatic juice also contains enzymes, namely trypsin and chymotrypsin which digest proteins, lipase digests lipids to 3 fatty acids and glycerol and amylase for digestion of carbohydrates.5. Gall bladder has three functions that are storage, concentration, and secretion of bile.

Bile salts are important for emulsification of fats: the fats are broken into small droplets, and this increases surface area for more lipases to breakdown the fats to easily absorbable forms. Bile salts are alkaline; they neutralize the HCl in the chyme as it moves to the duodenum. Liver is associated with gall bladder function because it produces bile juice.6. Chemical digestion and nutrient absorption in small intestines are dependent on each other digestive enzymes, and bile break food substances to absorbable materials which are absorbed into the blood systems through the walls of small intestines by either of these 3 processes - active transport, osmosis and diffusion, and in all the processes a concentration gradient must be maintained by continued digestion.7. Large intestine absorbs excess water back to the body and ions (Na+ Cl2-) liquid chyme is converted into semi solid feces for either storage or disposal.

The flora in large intestines is important for they produce enzymes that breakdown plant fiber (cellulose); since human beings cannot digest cellulose - we lack enzyme cellulose - this bacteria can break down the undigested fiber in fecal material and provide nutrients to the body .Yoghurt is important when taking antibiotics: it makes them more effective, dilutes the effect of antibiotics and replaces normal microorganisms that could be killed by the antibiotics.8. Celiac disease is genetic; symptoms of this are diarrhea, vomiting, constipation, fatty stool and weight loss.

Treatment is a gluten free diet. GERD is caused by abnormal lower esophageal or slow emptying of the stomach which causes ulcers, asthma and esophagitis. Symptoms are heartburn and nausea; treatment is antacids and proton pump inhibitors. IBD is caused by poor blood supply or auto immune responses; symptoms are inflammation of the colon; treatment is by surgery or use of drugs (mesalamine). Colon cancer is caused by excess gas; symptoms are gas, bloating and abdominal pain. Treatment is by use of drugs like stivagra which can cause liver toxicity.

ReferencesPinto, C. M. (2001). Pancrease exocrine functions. Retrieved from http://www.cristina.prof.ufsc.br/v2/digesterio/smith-morton-2001-pancrease-exocrine-05-elsevier.pdfLechman, Ch. (1999). What Is the Function of the Small Intestine? Retrieved from http://www.ehow.com/about-4570506-function-small_intestines-.html