The Endocrine, the Digestive, and the Cardiovascular Systems in the Digestion of a Chicken Sandwich

The Digestion of a Chicken Sandwich

The digestion of a typical meal begins with mastication then broken further into smaller pieces that can be absorbed into the bloodstream. The process of digestion is elaborate such that it takes a series of processes before energy in the form of ATP is synthesized in the body. This essay discusses the endocrine, the digestive, and the cardiovascular systems in the digestion of a chicken sandwich. It also discusses the process through which synthesized energy gets to the endocrine system. The task also explores the roles played by the digestive system as well as the absorption of the nutrients to synthesize energy from the substrate molecules.

The Digestion Process

The process of digestion begins in the mouth when the substrate is introduced into the system. Various organs are charged with the responsibility of digesting the substrates. Notably, the systems are designed such that they work together to break the food molecules into smaller pieces that can be utilized in the body in a state that can readily be taken into the bloodstream the utilized in the body. The absorption takes place in the gastrointestinal tract. The tract is a system that runs from the mouth through to the anus. The primary organs involved in the process of digestion include the gallbladder, the liver, and the pancreas among others. The GIT depends entirely in the hormonal system to initiate the breakdown of the substrate molecules into simpler forms. The chemical agents are located mainly throughout the system and include parts of the stomach, the pancreas, and the small intestine. The critical gastrointestinal hormones charged with the control of the digestive system include the Gastrin, Secretin and the Cholecystokinin (CKK). They collectively stimulate the releases of critical enzymes together with the digestive juices like the pancreatic and bile juices and the gastric acid from the stomach.

The Endocrine System and Digestive Enzymes

The endocrine system, with the help of enzymes, plays vital roles in the breakdown of substrates into smaller components that can be absorbed into the body. The digestive enzymes are secreted in the stomach, in the small intestines, and in the salivary glands. These enzymes are designed such that they work on particular substrates, thus the substrate specificity trait they possess. For instance, the enzyme amylase is designed to act on the breakdown of carbohydrates while the protease enzyme digests proteins. Lipase, on the other hand, digests fats.

The Process of Mechanical Digestion

It is useful to take note of the fact that before the intake of chicken sandwich, the process of digestion has begun. The sense of smell and the thought of having the food trigger the nervous system to relay the message to the salivary glands. This then stimulates the production of saliva that lubricates the mouth and the pharynx. Once the substrate gets its way into the mouth, the process of chemical and mechanical digestion sets the stage. This is the point at which the teeth begin grinding the sandwich through the process of mastication. The mechanical process involves tearing, chewing, and grinding of the sandwich which is the substrate in this case. The process takes place so that the surface area of the substrate can be increased. The tongue then mixes the food with saliva to form a bolus. The food contains amylase within it. The enzyme acts on the carbohydrates by breaking it into simpler forms of the di- and monosaccharides. The other components of saliva include water and mucus that are necessary for dissolving and lubricating the food. The mixed-up food is now in the form of bolus and is pushed back by the tongue to the back of the throat, the pharynx where the food triggers the swallowing process through a reflex action. This is where the food gets into the esophagus, and the process of gastric digestion begins.

The Stomach and Gastric Digestion

The esophagus refers to a tube connecting the stomach with the mouth. It should be noted that no any chemical or absorptive process takes place in the stomach. The bolus only passes through the stomach through the peristalsis and gets to the esophageal sphincter. The sphincter then relaxes in a rhythmic manner allowing room for the controlled quantities of the bolus to get to the stomach. While in the stomach, the chemical and mechanical processes of digestion continue. When the food enters into the stomach where the peristalsis process is initiated, and the mixing waves begin in the stomach. The food then gets mixed with the secreted enzymes plus the chemicals and helps in the reduction of the substrate to chyme. The churning process intensifies as the food gets to the stomach until it gets to the pylorus. At this point, the stomach makes it possible for only a small quantity of food to pass through into the duodenum via the pyloric sphincter.

The Role of Gastric Juices

Upon entering the stomach, the bolus triggers the secretion of the gastric juices which include hydrochloric acid (HCl) and the Pepsinogen which is the precursor of the enzyme Pepsin from the chief cells. It is useful to take note of the fact that pepsinogen is secreted in that form to avoid the auto-digestion of the stomach walls. The hydrochloric acid plus the intrinsic factor makes it possible to create the acidic condition of the stomach. In the process, mucus is also secreted by the mucosal neck cells. The HCl raises the pH of the stomach thereby making the condition very suitable for the functionality of the enzyme pepsin as it prepares to begin the process of breaking down the proteins into smaller components of amino acids. In the process, the mucus plays the role of protecting the stomach walls from the corrosive effects of the acid. The role of the intrinsic factor is to help in the absorption of the vitamin B12.

The Journey Through the Small Intestines

The churned food in the process is then pushed to the intestines where the chime goes past the pyloric sphincter to the duodenum. Duodenum is the first section of the small intestines. The chyme then goes to the small intestines with some traces of partially digested disaccharides and monosaccharides, the proteins into peptides and lipids into fatty acids and droplets. It is worth noting that this is the collective responsibility of the bile, the pancreatic, and intestinal juice to complete the process of digestion. As the churned food enters the small intestines, it initiates the release of the secret in hormone which in turn decreases the secretions of the gastric walls and sees to it that the release of the bicarbonates is done. The process neutralizes the corrosive effects of the acid in the stomach. The partnership of the digestive and endocrine systems act as the protectors of the small intestines. The cholecystokinin hormone is also known to initiate bile and pancreatic juice release. The juices play critical roles in the final processes of digestion before undergoing absorption.

Absorption of Nutrients

The unique aspect of the small intestines is the presence of the villi. These are the finger-like projections in the small intestines that help in increasing the surface area of the intestines for absorption of food molecules while at the same time having a network of blood capillaries as well as the lymph vessels that help in carrying out the same. The starch from bread that escapes digestion into maltose when the churned food enters the small intestines is then broken down into simpler components of the pancreatic amylase. Splitting the amylose into small fragments of sucrose, maltose, and lactose takes place. The molecules are then split into the common molecule in the name of glucose. This is the simplest form absorbable by the digestive system. The protein from chicken continues with the digestion process, with enzymes such as the trypsin, elastase, carboxypeptidase, and chymotrypsin involved in the process. The enzymes peptidases in the brush border, the dipeptidase and aminopeptidase bring the process to completion. The process of digesting the fat in the form of butter also ends in the small intestines. The bile, through the help of its salts, emulsifies the lipid globules, offering a large surface area that makes it possible for the pancreatic lipase to perform more effectively by breaking down the fat into absorbable forms of fatty acids.

The Energy Circulation Process

For the fully digested and absorbed sandwich chicken to be utilized in the body, glucose from the bread is made to pass into the lumen of the absorptive cells into the villi and then through the secondary transport system. The process goes alongside the transportation of the sodium ions (NA+). The molecules then move out through absorptive cells through the process of diffusion into the capillaries. The amino acids get absorbed into the epithelial cells through the active transport with the NA+. They then pass the cells through to the bloodstream. The fatty acids get diffused into the lacteals through diffusion as well. The bile salts also get absorbed via active transport into the ileum as well.

Energy Circulation in the Body

As the nutrients get into the bloodstream, they enter through the cytoplasmic cells where the process of respiration takes place. There are three main stages in the cytoplasmic respiration. These include glycolysis, electron transport system, and the Krebs cycle. While the process is mainly driven by the ATP molecules, the ADP molecules also form part of the elements that form the chemical energy. The process turns each of the glucose molecules into 36 adenosine triphosphate-ATP. These are the molecules of life. The process takes place in the mitochondria.

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