A. esophagus
B. stomach
C. duodenum
D. oral cavity
For those aiming to excel in their ATI TEAS test and secure admission into their desired nursing program, ExamGates offers an invaluable resource. Our platform features practice questions meticulously crafted by tutors who have previously aced the exam themselves. With ExamGates, you can access content that is 100% relevant to the test, accompanied by vivid images and illustrations. Additionally, our platform provides comprehensive explanations for both correct and incorrect answers, empowering you to fully grasp the material and optimize your study efforts. Take the first step towards your nursing aspirations with ExamGates today.
D. oral cavity
- Correct: Chemical digestion of carbohydrates begins in the oral cavity. Salivary glands in the mouth secrete saliva, which contains an enzyme called amylase. Amylase breaks down complex carbohydrates (such as starch) into simpler sugars (such as maltose) through hydrolysis. This process initiates the digestion of carbohydrates before the food bolus reaches the stomach or small intestine.
A. esophagus
- Incorrect: The esophagus is primarily involved in the propulsion of food from the mouth to the stomach through peristaltic contractions. It does not play a significant role in the chemical digestion of carbohydrates.
B. stomach
- Incorrect: While the stomach plays a role in the digestion of proteins through the action of gastric juices containing pepsin and hydrochloric acid, it does not contribute significantly to the digestion of carbohydrates. In fact, the acidic environment of the stomach may temporarily inhibit the activity of salivary amylase.
C. duodenum
- Incorrect: The duodenum is the first part of the small intestine where the majority of chemical digestion occurs. While the duodenum receives pancreatic enzymes and bile that aid in the digestion of carbohydrates, proteins, and fats, the initial chemical digestion of carbohydrates primarily occurs in the oral cavity with the action of salivary amylase.
Therefore, the Correct Answer is D.
Which of these statements about the pharynx is true?
A. It extends from the nasal and oral cavities superiorly to the esophagus anteriorly.
B. The oropharynx is continuous superiorly with the nasopharynx.
C. The nasopharynx is involved in digestion.
D. The laryngopharynx is composed partially of cartilage.
The Correct Answer is D.d) The laryngopharynx is composed partially of cartilage.
- True: The statement that the laryngopharynx is composed partially of cartilage is true. The pharynx, commonly known as the throat, is a muscular tube that extends from the base of the skull to the level of the sixth cervical vertebra. It serves as a passageway for both air and food. The pharynx is divided into three regions: the nasopharynx, oropharynx, and laryngopharynx.
a) It extends from the nasal and oral cavities superiorly to the esophagus anteriorly.
- False: The pharynx extends from the nasal and oral cavities superiorly to the esophagus and larynx inferiorly, not anteriorly.
b) The oropharynx is continuous superiorly with the nasopharynx.
- False: The oropharynx is continuous inferiorly with the oral cavity, not superiorly with the nasopharynx. The nasopharynx is continuous superiorly with the nasal cavity.
c) The nasopharynx is involved in digestion.
- False: The nasopharynx is primarily involved in respiration and the passage of air. It contains the openings of the auditory tubes and tonsils but is not directly involved in digestion.
Your digestive system works on the foods you eat for about:
A. 5 hours
B. 10 hours
C. 15 hours
D. 20 hours
The Correct Answer is B.The digestive system typically works on the foods you eat for about 10 hours. The entire process of digestion, from the moment food enters the mouth until waste is eliminated from the body, generally takes around 24 to 72 hours. However, the actual time it takes for food to move through the digestive tract and be fully digested varies depending on factors such as the type of food consumed, individual metabolism, and overall gastrointestinal health. On average, food spends approximately 4 to 6 hours in the stomach and small intestine, and another 12 to 36 hours in the large intestine before being eliminated as waste. Therefore, the total time for digestion and elimination is typically around 24 to 72 hours.
Which of the following organs has 3 layers of smooth muscle in its muscularis externa?
A. small intestine
B. esophagus
C. stomach
D. large intestine
The Correct Answer is C.C. stomach
- Correct: The stomach has three layers of smooth muscle in its muscularis externa, which is the muscular layer of the gastrointestinal tract responsible for peristalsis and mixing of food. These muscle layers are arranged in longitudinal, circular, and oblique orientations, allowing for the mechanical processing of ingested food and the propulsion of food through the digestive tract. This muscular arrangement contributes to the stomach's ability to churn and mix food with gastric juices during digestion.
A. small intestine
- Incorrect: While the small intestine does have smooth muscle in its muscularis externa, it typically has two layers of smooth muscle: an inner circular layer and an outer longitudinal layer.
B. esophagus
- Incorrect: The esophagus also has smooth muscle in its muscularis externa, but it typically has two layers of smooth muscle: an inner circular layer and an outer longitudinal layer.
D. large intestine
- Incorrect: The large intestine, like the small intestine, typically has two layers of smooth muscle in its muscularis externa: an inner circular layer and an outer longitudinal layer.
The pancreas, liver, and gallbladder help digestion in these ways, respectively:
A. making enzymes; making bile and processing nutrients; and storing bile
B. producing saliva; digesting carbohydrates; and eliminating waste
C. producing hormones; producing enzymes; and eliminating waste
D. making acids; producing digestive juices; and storing enzymes
The Correct Answer is A.a. making enzymes; making bile and processing nutrients; and storing bile
- Correct: The pancreas, liver, and gallbladder help digestion in the following ways:
1. The pancreas produces and secretes digestive enzymes into the small intestine to aid in the breakdown of carbohydrates, proteins, and fats. These enzymes include amylase (for carbohydrates), proteases (for proteins), and lipases (for fats).
2. The liver produces bile, a digestive fluid that emulsifies fats by breaking them down into smaller droplets, which increases the surface area for enzymes to act upon. The liver also processes nutrients absorbed from the small intestine, including carbohydrates, proteins, and fats.
3. The gallbladder stores and concentrates bile produced by the liver. When needed for digestion, the gallbladder releases bile into the small intestine via the common bile duct to aid in the emulsification and digestion of fats.
Therefore, option a accurately describes the roles of the pancreas, liver, and gallbladder in digestion.
In which organ of the human body is urea produced as a result of the breakdown of amino acids?
A. liver
B. pancreas
C. stomach
D. small intestine
The Correct Answer is A.A) liver
- Correct: Urea is produced in the liver as a result of the breakdown of amino acids. Amino acids are the building blocks of proteins, and when proteins are metabolized for energy or other purposes, their constituent amino acids are broken down in a process called deamination. During deamination, the amino groups (-NH2) are removed from the amino acids, forming ammonia (NH3). The liver converts ammonia into urea through a series of biochemical reactions known as the urea cycle. Urea is then excreted by the kidneys in the urine, helping to remove nitrogenous waste from the body.
B) pancreas
- Incorrect: The pancreas is an organ involved in the production of digestive enzymes and hormones such as insulin and glucagon. It is not primarily responsible for the production of urea from the breakdown of amino acids.
C) stomach
- Incorrect: The stomach is primarily involved in the mechanical and chemical digestion of food, particularly proteins. While protein digestion begins in the stomach with the action of gastric juices containing enzymes such as pepsin, urea production from the breakdown of amino acids occurs mainly in the liver.
D) small intestine
- Incorrect: The small intestine is primarily involved in the absorption of nutrients from digested food, rather than the production of urea from the breakdown of amino acids. While some amino acids may be absorbed in the small intestine, urea production primarily occurs in the liver.
Which of the following stimuli activates sensors in the walls of digestive organs?
A. breakdown products of digestion
B. distension
C. pH of chyme
D. all of the above
The Correct Answer is D.d) all of the above
- Correct: All of the listed stimuli activate sensors in the walls of digestive organs:
a) Breakdown products of digestion: The presence of breakdown products, such as nutrients and smaller molecules resulting from digestion, can activate sensors in the walls of digestive organs. These sensors help regulate various digestive processes and signal the release of digestive enzymes and hormones.
b) Distension: Distension, or stretching of the walls of the digestive organs, is a stimulus that activates sensors. It occurs as the volume of the digestive tract increases due to the presence of ingested food, and it triggers reflexes that coordinate muscular contractions for propulsion and mixing.
c) pH of chyme: The pH of the chyme (the semi-liquid mixture of food and digestive juices in the stomach and small intestine) is another stimulus that activates sensors. Changes in pH can signal the need for adjustments in the secretion of digestive enzymes and the regulation of gastric and intestinal functions.
Therefore, all of the mentioned stimuli play a role in activating sensors and regulating digestive processes in response to the specific conditions within the digestive organs.
During the process of absorption, nutrients from food go from:
A. the intestines into the bladder
B. the blood into the organs
C. the intestines into the bloodstream
D. the mouth into the stomach
The Correct Answer is C.c. the intestines into the bloodstream
- Correct: During the process of absorption, nutrients from food pass from the intestines into the bloodstream. After food is broken down into its constituent nutrients through digestion in the stomach and small intestine, these nutrients are absorbed across the lining of the small intestine into the bloodstream. The small intestine is highly specialized for absorption, with villi and microvilli increasing the surface area available for nutrient absorption. Once absorbed into the bloodstream, nutrients are transported to various organs and tissues throughout the body to provide energy, support growth and repair, and maintain overall health.
a. the intestines into the bladder
- Incorrect: The bladder is part of the urinary system and is responsible for storing urine produced by the kidneys. Absorption of nutrients does not involve passage into the bladder.
b. the blood into the organs
- Incorrect: While nutrients absorbed into the bloodstream are indeed transported to various organs and tissues throughout the body, absorption itself occurs in the intestines, not directly from the blood into the organs.
d. the mouth into the stomach
- Incorrect: The mouth and stomach are primarily involved in the initial stages of digestion, including mechanical breakdown of food and the initiation of chemical digestion of carbohydrates and proteins. Absorption of nutrients occurs primarily in the small intestine, not from the mouth into the stomach.
During gastric emptying, chyme is released into the duodenum through the ________.
A. esophageal hiatus
B. pyloric antrum
C. pyloric canal
D. pyloric sphincter
The Correct Answer is C.c) pyloric sphincter
- Correct: During gastric emptying, chyme (partially digested food) is released from the stomach into the duodenum through the pyloric sphincter. The pyloric sphincter is a muscular valve located at the junction between the stomach and the duodenum. It regulates the passage of chyme from the stomach into the small intestine, allowing for controlled release and preventing backflow of intestinal contents into the stomach.
a) pyloric antrum
- Incorrect: The pyloric antrum is the lower portion of the stomach that leads into the pyloric canal. It is involved in mixing and churning food, but it does not regulate the release of chyme into the duodenum.
b) pyloric canal
- Incorrect: The pyloric canal is the narrow portion of the stomach that connects the pyloric antrum to the pyloric sphincter. It is involved in directing chyme toward the pyloric sphincter for release into the duodenum, but it is not the site of chyme release itself.
The esophageal hiatus is an opening in the diaphragm through which the esophagus passes as it descends from the thoracic cavity into the abdominal cavity. It is not directly involved in gastric emptying.
In the stomach:
A. muscles churn and mix the food with acids and enzymes
B. glands make 3 quarts of digestive juices each day
C. food leaves as a thick liquid called chyme
D. all of the above
The Correct Answer is D.d. all of the above
- Correct: All of the statements are true regarding the stomach:
a. muscles churn and mix the food with acids and enzymes: The stomach has muscular walls that contract and relax to mechanically churn and mix food with gastric juices, including hydrochloric acid and various enzymes (such as pepsin) that aid in the digestion of proteins.
b. glands make 3 quarts of digestive juices each day: The gastric glands in the lining of the stomach produce gastric juice, which contains hydrochloric acid, enzymes (such as pepsinogen), mucus, and intrinsic factor. These glands collectively secrete about 2 to 3 liters (quarts) of gastric juice per day.
c. food leaves as a thick liquid called chyme: After mixing with gastric juices and undergoing partial digestion in the stomach, food is transformed into a semi-liquid mixture called chyme. Chyme is then gradually released from the stomach into the small intestine for further digestion and absorption.
Therefore, all of the statements accurately describe processes that occur in the stomach.
Pancreatic juice ________.
A. deactivates bile.
B. is secreted by pancreatic islet cells.
C. buffers chyme.
D. is released into the cystic duct.
The Correct Answer is C.c) buffers chyme.
- Correct: Pancreatic juice contains bicarbonate ions, which act as buffers to neutralize the acidic chyme entering the duodenum from the stomach. This neutralization is essential for maintaining the optimal pH for the activity of digestive enzymes in the small intestine.
a) deactivates bile.
- Incorrect: Pancreatic juice does not deactivate bile. Bile is not deactivated in the digestive process; instead, it aids in the emulsification and digestion of fats in the small intestine.
b) is secreted by pancreatic islet cells.
- Incorrect: Pancreatic juice is secreted by exocrine cells called pancreatic acinar cells, not by pancreatic islet cells. Pancreatic islet cells secrete hormones such as insulin and glucagon, which regulate blood glucose levels.
d) is released into the cystic duct.
- Incorrect: Pancreatic juice is released into the duodenum through the pancreatic duct, not the cystic duct. The cystic duct connects the gallbladder to the common bile duct, allowing bile to be released into the duodenum when needed for digestion.