To successfully complete this assignment, first read the following exercise from the Laboratory Manual: Exercise 38. Anatomy of the Digestive System.
Reference:
Marieb, E. N., Mitchell, S. J., & Smith, L. A. (2013). Human anatomy & physiology laboratory manual (11th ed.). [Fetal Pig version]. San Francisco, CA: Pearson Benjamin Cummings.
Student Discussion Assignment
- Trace and discuss the complete movement of a bolus of food entering and exiting the human via the digestive system.
- View the anatomical models Figure 38.6 (b),Figure 38.8 (b),and Figure38.14 (a)and(b)from Laboratory Manual and briefly identify the structures that are described by the following abbreviated statements. Post your brief responses in the threaded Discussion Area below:
- Smooth muscle layers of the muscularis
- Location and function of gastric pits
- Overall structure of the finger-like villi within the small intestine/increased absorption area
- Function and location of hepatic artery and vein
- Specific lobes of the liver
- Gallbladder relationship to bile and digestion
- View the histology slides Figure 38.6 (b),Figure 38.9 (a),and Figure 38.13in your Laboratory Manual and identify the microscopic structures indicated by a leader line, number, or bracket. In the threaded Discussion Area below, briefly describe the function of:
- Figure 38.6 (b) gastric glands
- Figure 38.9 (a) Brunner’s gland
- Figure 38.13 ductal cells
As in all assignments, cite your sources in your work and provide references for the citations in APA format. Support your work, using your course lectures and textbook readings. Helpful APA guides and resources are available in the South University Online Library. Below are guides that are located in the library and can be accessed and downloaded via the South University Online Citation Resources: APA Style page. The American Psychological Association website also provides detailed guidance on formatting, citations, and references at APA Style.
Expert Solution Preview
Introduction:
This assignment focuses on the anatomy of the digestive system. Students are required to trace and discuss the complete movement of a bolus of food entering and exiting the human body via the digestive system. They also need to view anatomical models and histology slides and identify the structures and functions of various parts of the digestive system. Students are expected to use their course lectures, textbook readings, and other credible sources to support their work.
Question 1:
The movement of a bolus of food entering and exiting the human body via the digestive system can be summarized as follows:
– Mouth: The process of digestion begins in the mouth where food is chewed and mixed with saliva containing enzymes that break down carbohydrates.
– Pharynx and Esophagus: The bolus of food is propelled into the pharynx and then into the esophagus by muscular contractions.
– Stomach: The bolus of food enters the stomach where gastric juices containing enzymes and acid break down proteins and kill bacteria.
– Small Intestine: The partially digested food enters the small intestine where enzymes from the pancreas and bile from the liver further break down fats, proteins, and carbohydrates. Nutrients are absorbed into the bloodstream through the lining of the small intestine.
– Large Intestine: The remaining waste products pass into the large intestine where water is absorbed and the feces are formed.
– Rectum and Anus: The feces are eliminated from the body through the rectum and anus.
Question 2:
a) Smooth muscle layers of the muscularis: The muscularis is a layer of tissue in the digestive tract that is responsible for moving food through the system. The smooth muscle layers of the muscularis are responsible for rhythmic contractions that help propel food along the digestive tract.
b) Location and function of gastric pits: Gastric pits are small openings in the stomach lining that lead to gastric glands. These glands secrete gastric juices containing enzymes and acid that break down proteins and kill bacteria.
c) Overall structure of the finger-like villi within the small intestine/increased absorption area: The villi are finger-like projections on the lining of the small intestine that increase the surface area available for nutrient absorption. Each villus contains a network of blood vessels and a lacteal (a lymphatic vessel) that absorb nutrients.
d) Function and location of hepatic artery and vein: The hepatic artery and vein are part of the hepatic portal system that carries blood from the digestive organs to the liver for processing. The hepatic artery carries oxygenated blood to the liver while the hepatic vein carries deoxygenated blood away from the liver.
e) Specific lobes of the liver: The liver has four lobes: the right lobe, left lobe, caudate lobe, and quadrate lobe.
f) Gallbladder relationship to bile and digestion: The gallbladder is a small, pear-shaped organ located under the liver. It stores and concentrates bile produced by the liver and releases it into the small intestine to aid in the digestion of fats.
Question 3:
a) Figure 38.6 (b) gastric glands: Gastric glands are located in the lining of the stomach and secrete gastric juices containing enzymes and acid that break down proteins and kill bacteria.
b) Figure 38.9 (a) Brunner’s gland: Brunner’s glands are located in the duodenum (the first part of the small intestine) and secrete mucus to protect the intestinal lining from acidic chyme (partially digested food) coming from the stomach.
c) Figure 38.13 ductal cells: Ductal cells are epithelial cells that line the ducts of the pancreas and secrete bicarbonate to neutralize acidic chyme coming from the stomach.
