Digestive System Assignment 2 Homework PDF

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Digestive System Assignment 1

Direction: Label the following • Gastroesophageal sphincter • Pyloric sphincter • Upper esophageal sphincter

Directions: Read and answer the following •

What role does the gastroesophageal sphincter play in digestion?

Answer: The gastroesophageal sphincter plays the role of a digestive disorder, which affects the lower esophageal sphincter. The sphincter muscle fails to close tightly, causing food and stomach acids to reflux into the esophagus. This eventually becomes inflamed, causing chest pain or a cough. •

What role does the pyloric sphincter play in digestion?

Answer: The pyloric sphincter is a band of smooth muscle at the junction between the pylorus of the stomach and the duodenum of the small intestine. It plays an important role in digestion, where it acts as a valve to controls the flow of partially digested food from the stomach to the small intestine. •

What role does the upper esophageal sphincter play in digestion?

Answer: The upper esophageal sphincter is a bundle of muscles at the top of the esophagus. The muscles of the upper esophageal sphincter are under conscious control, used when breathing, eating, belching, and vomiting. They keep food and secretions from going down the windpipe. •

Describe the mucosal barrier role in digestion?

Answer: The mucosa is the innermost layer, and functions in absorption and secretion. It is composed of epithelium cells and a thin connective tissue. The mucosa contains specialized goblet cells that secrete sticky mucus throughout the GI tract. •

Describe the passageway of food from ingestion to defecation starting with the mouth.

Answer: The first of these processes, ingestion, refers to the entry of food into the alimentary canal through the mouth. There, the food is chewed and mixed with saliva, which contains enzymes that begin breaking down the carbohydrates in the food plus some lipid digestion via lingual lipase. Chewing increases the surface area of the food and allows an appropriately sized bolus to be produced. Food leaves the mouth when the tongue and pharyngeal muscles propel it into the esophagus. This act of swallowing, the last voluntary act until defecation, is an example of propulsion, which refers to the movement of food through the digestive tract. It includes both the voluntary process of swallowing and the involuntary process of peristalsis. Peristalsis consists of sequential, alternating waves of contraction and relaxation of alimentary wall smooth muscles, which act to propel food along.

Directions: Read the description and match the correct term • Secrets mucus ___(Mucous Neck Cells) • Secrete HCL ___(Parietal Cells) • Produce pepsinogen ___(Chief Cells) •

Chief cells

B. Parietal Cells

C. Mucous Neck Cells

Directions: Read and answer •

Describe the passage of bile from the liver to the small intestine.

Answer: Bile flows out of the liver through the left and right hepatic ducts, which come together to form the common hepatic duct. This duct then joins with a duct connected to the gallbladder, called the cystic duct, to form the common bile duct. The common bile duct enters the small intestine at the sphincter of a ring-shaped muscle, located a few inches below the stomach. About half the bile secreted between meals flows directly through the common bile duct into the small intestine.

•

What is a portal triad?

Answer: Portal triads are composed of three major tubes. Branches of the hepatic artery carry oxygenated blood to the hepatocytes, while branches of the portal vein carry blood with nutrients from the small intestine. The bile duct carries bile products away from the hepatocytes, to the larger ducts and gall bladder. •

Describe the function of the gallbladder?

Answer: The gallbladder is part of the biliary tract. ... The gallbladder's absorbent lining concentrates the stored bile. When food enters the small intestine, a hormone called cholecystokinin is released, signaling the gallbladder to contract and secrete bile into the small intestine through the common bile duct. The gallbladder is an organ that is part of the human biliary system, which is involved with the production, storage and transportation of bile. Bile is a yellowish-brown fluid produced by the liver and used to break up and digest fatty foods in the small intestine •

How does bile leave the gallbladder (include the structures)?

Answer: The liver cells secrete the bile into small canals that lead to the common bile duct. From there, a smaller duct branches off and leads to the gallbladder. The common bile duct ends at the small intestine. The bile produced by the liver flows directly into the small intestine during a meal. •

Describe the function of the hepatopancreatic sphincter ?

Answer: The sphincter of the hepatopancreatic sphincter is a muscular valve that controls the flow of digestive juices (bile and pancreatic juice) through the ampulla of Vater into the second part of the duodenum. What is the purpose of the hepatopancreatic sphincter and where is it located? Directions: Match the correct hormone with its function • Causes the release of pancreatic juices ___(Secretin)

•

Causes release of bile from liver ___(CCK)

•

A. CCK

•

Describe the major function of the large intestine.

B. Secretin

Answer: The major function of the large intestine is to absorb water from the remaining indigestible food matter and transmit the useless waste material from the body.

* List the end product of protein, fat, carbohydrate, and nucleic acids digestions. Answer: The end product of protein digestion are amino acids unlike that of carbohydrate which maybe glucose, galactose or fructose. The end product of fat digestion are triglycerides, free fatty acids and glycerol....