Enzymes and enzymatic reactions

Enzymes and enzymatic reactions
Q1. The primary function of enzymes in the human body is to increase the rate at which a given biological reaction takes place. There are many different types of enzymes produced in the human body, and all catalyze a particular reaction i.e. enzymes work on specific substrates. They are found in body fluids including blood, saliva, and digestive juices. Some of the reactions that enzymes catalyze are digestion (enzyme amylase increases the rate at which starch is broken down to maltose) and blood clotting (enzyme thrombin increases the rate of clotting) (Frey and Hegeman).
Q2. The enzyme amylase is produced by the salivary glands (salivary amylase) and in the pancreas (pancreatic amylase). Salivary amylase breaks down starch in the mouth into maltose which is absorbed by the body into the bloodstream. All the carbohydrates in the food cannot be exhaustively digested in the mouth. Pancreatic amylase moves to the small intestines through ducts where it completes the digestion of carbohydrates by breaking them into glucose which is absorbed into the bloodstream. This completes the digestion of carbohydrates (Frey and Hegeman).
Q3.Competitive inhibition is the situation where both the substrate and the inhibitor are struggling to get bound to the active sites of the enzymes. Enzymes have active sites. It is at this sites that substrate is bound during a reaction. This site is specific to a particular type of substrate. An inhibitor is any material other than the substrate that attaches itself to the active site of an enzyme preventing the substrate from connecting to the site and therefore decreasing the rate of reaction.

An active site can only take either the inhibitor or the substrate at a time. The choice depends on the affinity of inhibitor or the substrate. The one with the high affinity wins the day. Competitive inhibitors, unlike non-competitive inhibitors, do not permanently attach to the active site (Frey and Hegeman).
Q4. Coenzymes are a type of cofactors. They bind the active sites of the enzymes helping them function. They are organic in nature implying that they contain carbon atoms in their structure. Mainly they are obtained from vitamins, for example, folic acid. However, a few are not obtained from vitamins for example S-adenosyl methionine used by bacteria, eukaryotes, and archaea. They bind loosely to these active sites, unlike other cofactors. They recognize, attract or repulse a product or a substrate. Unlike enzymes, coenzymes cannot function on their own. They have to work alongside enzymes to increase the rate of biological reactions in the body. An example is vitamin B which assists in the formation of proteins and fats (Frey and Hegeman).
Q5.when the substrate of the enzyme is almost entirely used, the rate of the chemical reaction reduces. At this time, the enzymes are in excess as compared to the substrate and therefore some of the active sites of the enzymes have no substrate to work on. Before this stage, all the substrate was more than the enzyme, and their reaction rate was at its peak. We can, therefore, say that the reaction rate has decreased (Frey and Hegeman).

Works cited
Frey, Perry A. and Adrian D. Hegeman. Enzymatic Reaction Mechanisms. 1st ed. Oxford: Oxford University Press, 2007. Print.