Chemical reactions involve the rearranging of theconstituent atoms to create different substances. There are 6 clues to tell ifa chemical reaction has formed. Normally chemical reactions will displayseveral of these qualities:  an insolubleprecipitate is formed, bubbles are formed, color change is observed, new odoris produced, temperature change, light is produced.

Compounds that react witheach other are called reactants, compounds produced are called products andproducts that are solids are called precipitates. Subscripts are used to balancea compound in a reaction, while coefficients are used to balance the entireequation in order to satisfy the Law of Conservation of Mass.  The process of digestion is the act of converting food intochemical substances that the body can absorb into the blood stream to beutilized by body tissue. This happens when proteins, lipids, carbohydrates arebroken down into simpler compounds for the human body to process (“DigestiveSystem,” n.

d.). Food begins the digestive journey as soon as it isingested.  It is masticated (chewed up)in the mouth then swallowed and pushed down the esophagus with the help ofperistaltic contractions. The stomach breaks up the bolus chemically andmechanically. The nutrients in chyme is then absorbed in the small intestine,after which it travels through the large intestine and to the anus to beexcreted.

(“Enzymatic digestion,” n.d.) Digestion starts in the mouth where food is masticated(chewed) into smaller pieces. Saliva is rich in amylase, a salivary enzyme thatbreak down carbohydrates turning them into maltose, maltotriose and dextrins.

(“How Is Starch Changed by the Saliva in the Mouth?” n.d.). The enzyme coatseach starch molecule, and deconstructs it through hydrolysis to turn them intosmaller, more manageable pieces. This separation of long chained starches intosugars makes it easier to break down later in the body.  The esophagus is a muscular tube, roughly 8 inches inlength, that is lined with a layer of pink tissue called mucosa. It connectsthe pharynx to the stomach and transports the bolus of food away from themouth.  Automated muscle contractions,peristalsis, pushes food along the tube.

There are sphincters located at bothends of the esophagus, which open and close after swallowing, when food isabout to enter the stomach or when gas needs to be expelled. (“NormalFunction,” n.d.

).  The stomach is where the majority of digestion takes place.Chemical and mechanical forces break down the bolus and prepare it for furtherdigestion in the small intestine. Gastric juice, comprised of hydrochloricacid, water, electrolytes, mucus and an intrinsic factor, is responsible forthe digestion of proteins and fats. The enzymes pepsin and protease, secretedby stomach lining, breaks down proteins, converting them to peptides which arefurther digested by gastric lipase.

These stomach enzymes uncoil proteinsstrands as part of digestion. Trypsin breaks down protein strands into one twoor three amino acids. (“What Digests First, Protein, Carbohydrates or Fat?”n.d.).

Hydrochloric acid secreted by parietal cells converts pepsinogen intopepsin and breaks down various nutrients in food. It also kills more bacteriain food with its high acidity.  Unlike intramolecular forces which hold a single moleculetogether, intermolecular forces are responsible for the attraction betweencompounds. There are 3 types of intermolecular forces; London dispersionforces, dipole-dipole forces and hydrogen bonding (Meyers, n.d.). Londondispersion forces- a temporary force of attraction that occurs due to constantshifting of electrons in opposite molecules. This force is the weakest out of the three and occurs between allmolecules, regardless of whether they are polar or not.

Dipole-dipole forces- apermanent force of attraction between the positive end of one polar moleculeand the negative end of another polar molecule.  Hydrogen bonding- the strongest force of attraction that canoccur between two molecules. Hydrogen bonding occurs between a slightlypositive hydrogen on one molecule and a slightly negative atom on anothermolecule. The reason this bonding type is so strong is because the atomicradius of hydrogen is very small, allowing other atoms to come extremely close,however this only happens when hydrogen bonds with fluorine, oxygen ornitrogen. HCl(aq) is a polar molecular. Holding the moleculetogether is London dispersion forces and dipole-dipole forces as the positiveends of each molecule attracts the negative ends.

This force is permanent andstronger than London dispersion forces which are only temporary attractions dueto shifting (B, n.d.) Hydrochloric acid is extremely acidic with a pH of about 2.Our stomach lining is protected by a thick layer of mucus, however gastric acidcan burn through flesh and metals. Sodium bicarbonate (NaHCO3), secreted by thepancreas, is a weak base with a pH of about 8.4. It neutralizes gastric acidand is found in common foods. An example of a neutralization reaction that will occur inthe stomach as a result of gastric acid coming into contact with the bodiesnatural antacid is: HCL(aq) + NaHCO3(aq) ? NaCl(aq) + H2O(l) + CO2(g)Hydrochloric acid plus sodium bicarbonate yields sodiumchloride, water and carbon dioxide.

This double displacement and neutralizationreaction does occur as a gas and water are produced (gas, water or precipitatemust be a product of double displacement reaction for it to occur).   There are 5 types of chemical reactions: synthesis,decomposition, single displacement, double displacement and combustion. Doubledisplacement reactions are a chemical reaction in which the positive ions oftwo ionic compounds switch places to form two new ionic compounds. They mustalways produce either a solid, water or gas for a reaction to occur. Neutralizationreactions are a type of double displacement reaction in which an acid reactswith a base to produce an ionic compound (salt) and water. Acid base reactionsin the stomach are examples of neutralization reactions such as whenhydrochloric acid reacts with sodium bicarbonate.  Alongside the main GI tract, are other organs that help todigest food and filter out nutrients from waste.

The liver filters toxins out of the blood and produces bilewhich is used to further digestion. The gallbladder stores bile from the liverand holds it until it is needed. The pancreas secrets enzymes used in the smallintestine necessary for digestion. It also makes hormones that regulate theglucose levels in the blood (“Anatomy of the Liver, Gallbladder &Pancreas,” n.d.). The liver is a roughly triangular organ, capable ofregenerating itself.  It is divided upinto 4 distinct lobes; the left, right, caudate, and quadrate lobes.

The liverplays an important role in digestion with the production of bile. Bile is amixture of water, bile salts, cholesterol and bilirubin. It is able to emulsifylarge quantities of fat and break them up into smaller pieces, that are easierto digest (“Liver – Anatomy and Function of the Human Liver,” n.d.

). Detoxificationof blood also occurs in the liver when blood passes through the hepatic portal.Hepatocytes continuously monitor and eliminate toxins such as alcohol anddrugs.  The gallbladder is a small, green sac located under theliver that stores bile. The absorbent lining of the gallbladder makes it idealfor collecting excess amounts of bile until it is needed for digestion.

Whenfood enters the small intestine a hormone called cholecystokinin triggers thebile ducts leading out the gallbladder to open and deliver bile. The secretedbile helps to break up fats and drain waste products from the liver and excretethem (“Gallbladder Function, Location & Anatomy,” 2014). The pancreas is an organ located in the abdomen that isresponsible for converting digested food into fuel for cells. It has two mainfunctions, aid digestion (exocrine) and regulate blood sugar (endocrine). Exocrinefunction: the pancreas produces vital enzymes to aid digestion such as trypsinand chymotrypsin to breakdown proteins, amylase for carbohydrates and lipase tobreak down fats.

These juices enter the first part of the small intestine(duodenum). In addition, bile from the liver to help digest fats, proteins andstarches (“The Pancreas Center,” n.d.). Most of the process of digestion in the gastroenterologicaltract occurs in the small intestine. It is roughly 7.0 m long and is dividedinto three sections: the duodenum, jejunum, and ileum. The small intestine breaksdown and absorbs various nutrients from chyme and transports it throughout thebody.

  Villi (finger like extensions onthe small intestine wall) absorb passing nutrients and send it off to the bloodstream and other tissues (“Digestive System,” 2014). Most digestive enzymesenter the small intestine through the pancreatic duct. Proteolytic enzymes,including trypsin and chymotrypsin rip apart proteins into smaller peptides.  Duodenum – This is the first part of the small intestine aswell as the shortest. It deals with partially digested chyme from the stomachand plays a vital role in digestion. Chemical secretions from the liver,pancreas and gallbladder bring in enzymes to facilitate chemical digestion. Themuscular walls of the duodenum are lined with mucosa and epithelial tissue andmicrovilli to increase surface area for absorption.  Bile produced in the liver and stored in thegallbladder emulsifies lipids, breaking them into globular pieces to increasesurface area (“Duodenum – Small Intestine,” n.

d.).   There are three main enzymes secreted by the pancreas thatwork in the duodenum, one being trypsin.

As a proteolytic enzyme (proteindigesting enzyme), trypsin’s main function is to break the bonds of specificamino acids to produce peptides (“Trypsin,” n.d.). It also makes the absorptionof vitaminB12 an easier task. The combination of the slightly alkalineenvironment of pH 8 optimizes efficiency of the enzyme. Trypsin catalyzes thehydrolysis of peptide bonds, breaking down proteins into smaller pieces(“Trypsin,” 2018).   Dipeptide + H2O -> 2 Amino AcidsHydrolysis: a double displacement reaction involving waterin which the H2O molecule cleaves in half another molecule.

Consequently, onehalf of the molecule gets a H+ ion while the other half has the OH- ion. Inbiochemistry hydrolysis is used to break down polymers into monomers. Foodingested takes the form of a polymer which is digested by enzymes who’sreactions are sped up using hydrolysis. Monomers produced are small enough forthe body absorb (“Structural Biochemistry/Enzyme CatalyticMechanism/Hydrolysis,” n.d.). A periodic trend that describes the tendency of an atom to attracta bonding pair of atoms. Each atom on the periodic table has anelectronegativity value (EN).

The difference in EN in a bond can be used topredict the type of bond it will form. Covalent bonds share electrons, so theEN difference would be smaller, whereas ionic bonds that transfer electronsshould have a high EN difference.  There are 3 criteria that must be meet in order for achemical reaction to occur.  Reactantsmust: collide, collide with proper orientation, collide with enough energy.

 Things that can speed up a reaction include: acatalyst, increase in temperature, stirring, increasing surface area and more.  H2O is a covalent compound as it has an EN of 1.5 making ita polar covalent molecule. Water has all three types of intermolecular forces,London dispersion, dipole-dipole and hydrogen bonding, with the strongest and mostprevalent being the latter. Water has a pH of 7 making it safe to consume dueto its unreactive nature.

With the proper orientation and speed, the collisiontheory allows for two oxygen molecules to bond when the negative dipole meetsthe positive side.   Jejunum – The middlesegment of the small intestine.  Withepithelial cells and layers of villi along folded inner walls, the jejunum isresponsible for the majority of nutrient absorption in the digestivesystem.  After passing through this sectionof the small intestine, more than 90% of all nutritional content has beenabsorbed into the body. Ileum-  At 3.5m long,the Ileum is the longest and final segment in the small intestine. Its primaryfunction is to absorb vitaminB12 and reabsorb conjugated bile salts.

The innerwall is smoother than previous sections and has slower peristalticcontractions, in addition to being less permeable. To prepare food for excretion,there are patches of lymphatic tissue designed to detect and extract vitaminB12(“Ileum,” 2015).   The large intestine is a 1.8m long tube that prepares foodfor excretion. It is broken up into four parts: the ascending colon, thetransverse colon, the descending colon and the sigmoid colon.

First, water andsalts are removed from the waste as it passes through the colon during a periodof 36 hours. The waste makes its way to the sigmoid where it is stored untildefecation (“Large Intestine – Anatomy and Physiology,” n.d.).

Like the smallintestine, the colon is made up of four layers of tissue, each coated withvilli, mucosa or epithelial cells to remove any final nutrients. A variety ofbacteria is mixed with with the chyme to begin turning it into feces. Bacterialfermentation releases vitamins K, B1, B2, B6, B12, and biotin, as well ascreates flatulence (gas) from the methane and carbon dioxide in the bowel(Bradford, 2016).  The rectum is the last part of the digestive system rightbefore the anus and is about 10cm-15cm long.

It’s function is to temporarilystore feces. The muscular pouch holding excrement is able to expand toaccommodate more waste. When waste is about to be expelled, the internalsphincter relaxes and involuntary and voluntary muscle contractions beginworking (“Rectum Anatomy, Diagram & Function,” 2015).  Ultrasound Technician – An ultrasound technician operatesequipment that uses high frequency sound waves to create images of a patientsinternal organs. The work done helps doctors make decisions on patienttreatment, based on any abnormalities present in the imagery. Thesestechnicians work directly with patients and doctors and can specialize infields such as obstetric and gynecologic, abdominal, breast, vascular, orcardiac sonography (McKay, n.d.).

 Gastroenterologist – A physician with dedicated training andexperience who has studied in the management of diseases of thegastrointestinal tract and liver. These doctors can treat a variety ofconditions from Hepatitis C to irritable bowel syndrome (IBS). There arevarious fields of study, as some physicians may choose to specialize inhepatology, transplantation or other (“What Is a Gastroenterologist,” n.d.).

Theymay perform endoscopic procedures in which special instruments are used to viewones GI tract. Gastroenterologists do not perform surgery however, they canwork alongside a GI surgeon or provide treatment and advice to patients.