1.
Which of following processes is the function of the smooth muscle layer of the digestive system?
Correct Answer
C. Mixing and propulsion
Explanation
The smooth muscle layer of the digestive system is responsible for mixing and propelling food along the digestive tract. This layer contracts and relaxes to create rhythmic movements called peristalsis, which helps to mix the food with digestive enzymes and move it through the esophagus, stomach, and intestines. This process ensures that the food is thoroughly broken down and absorbed by the body.
2.
Which of following processes is the primary function of the mouth?
Correct Answer
A. Ingestion
Explanation
The primary function of the mouth is ingestion. Ingestion refers to the process of taking in food or drink through the mouth. It involves the intake of food and the initial breakdown of food particles by chewing and mixing with saliva. This process prepares the food for further digestion and absorption in the digestive system.
3.
Which of following processes is the primary function of the villi of the small intestine?
Correct Answer
C. Absorption
Explanation
The primary function of the villi of the small intestine is absorption. The villi are finger-like projections that increase the surface area of the small intestine, allowing for more efficient absorption of nutrients from digested food. The villi are lined with specialized cells called enterocytes, which have microvilli on their surface that further increase the surface area for absorption. These cells absorb nutrients such as glucose, amino acids, and fatty acids, as well as vitamins and minerals, and transport them into the bloodstream for distribution to the rest of the body.
4.
Which of the following accessory organs produces a fluid to soften food?
Correct Answer
B. Salivary glands
Explanation
The salivary glands produce a fluid called saliva, which helps soften food. Saliva contains enzymes that begin the process of breaking down carbohydrates in the food, making it easier to swallow and digest. The saliva also helps to lubricate the food, allowing it to be easily moved around the mouth and down the throat. Therefore, the salivary glands play a crucial role in the initial stages of digestion by producing a fluid that softens the food.
5.
Which of the following accessory organs produces a fluid that functions to emulsify dietary fats?
Correct Answer
C. Liver
Explanation
The liver produces a fluid called bile, which functions to emulsify dietary fats. Bile breaks down fats into smaller droplets, increasing their surface area and making it easier for enzymes to digest them. This process is important for the absorption and utilization of fats in the body. The teeth and salivary glands play a role in the initial mechanical breakdown and chemical digestion of food, but they do not produce a fluid specifically for emulsifying fats.
6.
Which of the following accessory organs stores bile?
Correct Answer
C. Gallbladder
Explanation
The gallbladder is the correct answer because it is an accessory organ that stores bile. Bile is produced by the liver and then stored in the gallbladder before being released into the small intestine to aid in the digestion and absorption of fats. The gallbladder acts as a storage reservoir for bile and releases it as needed.
7.
The capability of the GI tract to move material along its length is called
Correct Answer
A. Motility
Explanation
Motility refers to the ability of the gastrointestinal (GI) tract to move material along its length. This includes the contraction and relaxation of the muscles in the GI tract, which helps to propel food and waste products through the digestive system. Motility is essential for proper digestion and absorption of nutrients, as well as the elimination of waste. Propulsion, on the other hand, specifically refers to the movement of material in one direction through the GI tract.
8.
This layer of the GI tract is composed of areolar connective tissue containing blood and lymph vessels.
Correct Answer
B. Lamina propria
Explanation
The lamina propria is a layer of the gastrointestinal (GI) tract that is composed of areolar connective tissue. It contains blood and lymph vessels, which are important for the transport of nutrients and immune cells. The lamina propria is located within the mucosa layer of the GI tract, which also includes the epithelial lining and the muscularis mucosae. MALT (mucosa-associated lymphoid tissue) refers to lymphoid tissue that is found within the lamina propria, but it is not the correct answer to this question.
9.
This layer of the GI tract is composed of areolar connective tissue that binds the mucosa to the muscularis.
Correct Answer
A. Submucosa
Explanation
The submucosa is the correct answer because it is the layer of the GI tract that is composed of areolar connective tissue and it binds the mucosa to the muscularis. The submucosa provides support and nourishment to the mucosa, as well as contains blood vessels, lymphatics, and nerves.
10.
This layer functions by secreting a lubricating fluid.
Correct Answer
A. Serosa
Explanation
The correct answer is Serosa. The serosa is a layer of tissue that covers organs in the abdominal cavity and secretes a lubricating fluid. This fluid helps to reduce friction and allows the organs to move smoothly against each other. The serosa is important for protecting and supporting the organs in the abdominal cavity.
11.
These are composed of prominent lymphatic nodules that function in the immune response.
Correct Answer
C. MALT
Explanation
MALT stands for Mucosa-Associated Lymphoid Tissue. It is composed of prominent lymphatic nodules that function in the immune response. MALT is found in various mucosal tissues throughout the body, such as the respiratory tract, gastrointestinal tract, and genitourinary tract. These lymphoid nodules contain immune cells, such as lymphocytes, that help protect the mucosal surfaces from pathogens and foreign substances. MALT plays a crucial role in the body's defense against infections and maintaining immune homeostasis at mucosal sites.
12.
This plexus is located between the longitudinal and circular smooth muscle layers of the muscularis.
Correct Answer
B. Myenteric plexus
Explanation
The myenteric plexus is located between the longitudinal and circular smooth muscle layers of the muscularis. It is part of the enteric nervous system (ENS) and is responsible for regulating the motility of the gastrointestinal tract. It controls the contraction and relaxation of the muscles, allowing for the movement of food through the digestive system. The submucosal plexus, on the other hand, is located in the submucosa layer and is responsible for regulating secretions and blood flow in the digestive tract.
13.
Why do emotions such as anger or fear slow digestion?
Correct Answer
C. Because they stimulate the sympathetic nerves that supply the GI tract
Explanation
Emotions such as anger or fear can activate the body's fight-or-flight response, which is regulated by the sympathetic nervous system. When this system is activated, it redirects blood flow away from the digestive system and towards the muscles, heart, and lungs in preparation for physical action. This diversion of blood flow can slow down digestion, as the GI tract receives less blood and therefore less oxygen and nutrients. Therefore, the correct answer is that emotions such as anger or fear slow digestion because they stimulate the sympathetic nerves that supply the GI tract.
14.
This portion of the peritoneum drapes over the transverse colon and coils of the small intestine.
Correct Answer
A. Greater omentum
Explanation
The correct answer is the greater omentum. The greater omentum is a fold of peritoneum that hangs down from the stomach and drapes over the transverse colon and coils of the small intestine. It functions to store fat and provide protection to the abdominal organs. The falciform ligament attaches the liver to the anterior abdominal wall, while the lesser omentum connects the liver to the lesser curvature of the stomach and the beginning of the duodenum.
15.
This portion of the peritoneum attaches the liver to the anterior abdominal wall and diaphragm.
Correct Answer
B. Falciform ligament
Explanation
The falciform ligament is a thin, flat ligament that attaches the liver to the anterior abdominal wall and diaphragm. It is located in the midline of the abdomen and divides the liver into two lobes. The falciform ligament also contains a remnant of the fetal umbilical vein, known as the ligamentum teres. This ligament helps to stabilize the liver and provide support to the abdominal organs. The greater omentum and lesser omentum are other peritoneal attachments, but they do not specifically attach the liver to the anterior abdominal wall and diaphragm.
16.
This portion of the peritoneum is largely responsible for carrying blood and lymph vessels to the intestines.
Correct Answer
C. Mesocolon
Explanation
The mesocolon is the portion of the peritoneum that connects the colon to the posterior abdominal wall. It contains blood vessels, lymph vessels, and nerves that supply the intestines. It helps to support and suspend the colon in the abdominal cavity, allowing for movement and proper functioning of the intestines. Therefore, it is largely responsible for carrying blood and lymph vessels to the intestines.
17.
The hard palate
Correct Answer
C. All of the above
Explanation
The hard palate is the bony structure that forms the roof of the mouth. It is covered by a mucous membrane, which helps to keep the area moist and protected. Therefore, both options a and b are correct. "All of the above" is the correct answer because it includes both options a and b, making it the most comprehensive and accurate choice.
18.
In the mouth, this runs posteriorly to the sides of the pharynx.
Correct Answer
C. PalatopHaryngeal arch
Explanation
The palatopharyngeal arch runs posteriorly to the sides of the pharynx in the mouth.
19.
In the mouth, the tooth sockets are lined with
Correct Answer
C. Periodontal ligament
Explanation
The tooth sockets in the mouth are lined with the periodontal ligament. This ligament is a fibrous connective tissue that surrounds the root of the tooth and attaches it to the surrounding bone. It helps to support the tooth and absorb the forces generated during chewing and biting. The periodontal ligament also plays a role in maintaining the health of the tooth and surrounding tissues by providing a barrier against bacteria and other harmful substances.
20.
Deciduous molars are replaced by
Correct Answer
A. Bicuspids
Explanation
Deciduous molars are the primary teeth that are eventually replaced by permanent teeth. The correct answer, bicuspids, refers to the premolars, which are the teeth that come after the deciduous molars and before the molars. Bicuspids have two cusps or points on their chewing surface and are responsible for grinding and chewing food. Therefore, they are the teeth that replace the deciduous molars in the dental development process.
21.
Which of the following contains skeletal muscle?
Correct Answer
A. UES standard abbreviations
Explanation
The UES (Upper Esophageal Sphincter) contains skeletal muscle. The UES is a muscular ring located at the top of the esophagus, and it helps to control the passage of food and liquids into the throat. Skeletal muscle is a type of voluntary muscle that is under conscious control, and it is responsible for movements such as walking, talking, and swallowing. Therefore, the UES, which is involved in the swallowing process, contains skeletal muscle.
22.
How many stages of deglutition are there?
Correct Answer
B. 3
Explanation
There are three stages of deglutition. Deglutition refers to the process of swallowing. The three stages include the oral phase, pharyngeal phase, and esophageal phase. In the oral phase, food is chewed and mixed with saliva to form a bolus. The pharyngeal phase involves the movement of the bolus from the back of the mouth into the throat and down the esophagus. Lastly, in the esophageal phase, the bolus is pushed down the esophagus and into the stomach.
23.
This structure of the stomach allows greater distension for food storage.
Correct Answer
B. Rugae
Explanation
The rugae refers to the folds or wrinkles in the stomach lining that allow it to expand and stretch when food is consumed. These folds increase the surface area of the stomach, allowing for greater distension and storage of food. This enables the stomach to accommodate larger amounts of food and aids in the digestion and absorption process. The pylorus is the lower part of the stomach that connects to the small intestine, and the sphincter is a ring-like muscle that controls the passage of food between different parts of the digestive system. However, neither of these structures specifically contribute to the greater distension for food storage as the rugae does.
24.
Which of the following secrete gastric acid?
Correct Answer
B. Parietal cells
Explanation
Parietal cells are responsible for secreting gastric acid in the stomach. They produce hydrochloric acid, which helps in the digestion of food and also kills bacteria present in the stomach. Mucous cells, on the other hand, secrete mucus to protect the stomach lining, while chief cells secrete pepsinogen, an inactive form of the enzyme pepsin, which helps in the breakdown of proteins. However, the main function of secreting gastric acid is performed by parietal cells.
25.
This cell secretes the hormone that promotes production of gastric acid.
Correct Answer
C. G cell
Explanation
The G cell is the correct answer because it secretes the hormone that promotes the production of gastric acid.
26.
How long can food stay in the fundus before being mixed with gastric juices?
Correct Answer
C. 1 hour
Explanation
Food can stay in the fundus for up to 1 hour before being mixed with gastric juices. The fundus is the upper part of the stomach, where food is initially stored after ingestion. During this time, the food undergoes mechanical digestion through churning and mixing movements. After approximately 1 hour, the food gradually moves into the lower part of the stomach, called the antrum, where it is further broken down and mixed with gastric juices for chemical digestion.
27.
This major duct carries a fluid rich in bicarbonate ions.
Correct Answer
A. Pancreatic duct
Explanation
The correct answer is the pancreatic duct because it is the major duct that carries a fluid rich in bicarbonate ions. The other options, hepatopancreatic duct and cystic duct, do not carry a fluid rich in bicarbonate ions.
28.
Which of the following gastric enzymes digests proteins?
Correct Answer
B. Pepsin
Explanation
Pepsin is the correct answer because it is a gastric enzyme that specifically digests proteins in the stomach. Lipase, on the other hand, is an enzyme that digests fats. Therefore, pepsin is the correct choice for a gastric enzyme that digests proteins.
29.
This is the heaviest gland of the body.
Correct Answer
B. Liver
Explanation
The liver is the correct answer because it is the heaviest gland in the body. The liver is a large organ located in the upper right side of the abdomen and it plays a crucial role in various metabolic processes. It produces bile, which helps in the digestion of fats, and also filters toxins from the blood. Additionally, the liver stores vitamins and minerals, produces blood-clotting proteins, and helps regulate blood sugar levels. Due to its size and numerous functions, the liver is considered the heaviest gland in the body.
30.
This is found on the liver and is a remnant of the umbilical cord in a fetus.
Correct Answer
C. Round ligament
Explanation
The round ligament is found on the liver and is a remnant of the umbilical cord in a fetus. It connects the liver to the anterior abdominal wall and helps to support the liver in its position.
31.
This is the principle bile pigment.
Correct Answer
B. Bilirubin
Explanation
Bilirubin is the correct answer because it is the principle bile pigment. Bile pigments are produced when red blood cells are broken down in the liver. Bilirubin is then excreted in bile and gives stool its characteristic brown color. Stercobilin is a breakdown product of bilirubin and contributes to the brown color of stool, but it is not the principle bile pigment. Therefore, the correct answer is Bilirubin.
32.
Which of the following is NOT a function of the liver?
Correct Answer
C. Storage of bilirubin
Explanation
The liver performs various functions in the body, including the conversion of carbohydrates, protein metabolism, and the storage of certain substances. However, the storage of bilirubin is not a function of the liver. Bilirubin is a yellow pigment produced during the breakdown of red blood cells and is primarily stored in the gallbladder. The liver plays a role in the metabolism and excretion of bilirubin, but it does not store it.
33.
Which of the following small intestine cells secrete lysozyme?
Correct Answer
C. Paneth cells
Explanation
Paneth cells are specialized epithelial cells located in the crypts of Lieberkühn in the small intestine. They secrete various antimicrobial substances, including lysozyme. Lysozyme is an enzyme that helps protect the small intestine from bacterial infections by breaking down the cell walls of certain bacteria. This secretion of lysozyme by Paneth cells plays a crucial role in maintaining the overall health and integrity of the small intestine.
34.
Brunner’s glands
Correct Answer
C. Both mucous and an alkaline juice
Explanation
Brunner's glands secrete both mucous and an alkaline juice. The mucous helps to protect the lining of the duodenum from the acidic chyme coming from the stomach, while the alkaline juice helps to neutralize the acidity of the chyme. This combination of mucous and alkaline juice helps to create an optimal environment for digestion and absorption of nutrients in the small intestine.
35.
Which of the following enzymes acts to produce monoglycerides as products?
Correct Answer
A. Lipase
Explanation
Lipase is the correct answer because it is an enzyme that specifically acts on lipids, breaking them down into fatty acids and glycerol. In the process, lipase produces monoglycerides as one of the products. Amylase and trypsin, on the other hand, are enzymes that act on carbohydrates and proteins respectively, not lipids.
36.
Which of the following pancreatic enzymes acts to produce monosaccarides?
Correct Answer
B. Amylase
Explanation
Amylase is the correct answer because it is a pancreatic enzyme that acts to produce monosaccharides. Amylase specifically breaks down complex carbohydrates, such as starch and glycogen, into smaller units called monosaccharides. This process is important for the digestion and absorption of carbohydrates in the small intestine. Chymotrypsin and trypsin are pancreatic enzymes that primarily function to break down proteins.
37.
Which of the following pancreatic enzymes acts to produce smaller peptides from proteins?
Correct Answer
A. Chymotrypsin
Explanation
Chymotrypsin is a pancreatic enzyme that acts to produce smaller peptides from proteins. It functions by cleaving peptide bonds at specific amino acid residues, resulting in the breakdown of proteins into smaller peptide fragments. This process is essential for the digestion and absorption of proteins in the small intestine. Amylase, on the other hand, is responsible for the breakdown of carbohydrates, while pepsin is a stomach enzyme that digests proteins into smaller peptides.
38.
This hormone functions to counteract the effect of gastric acid in the small intestine.
Correct Answer
A. Secretin
Explanation
Secretin is a hormone that is released by the duodenum in response to the presence of acidic chyme from the stomach. It acts to counteract the effect of gastric acid by stimulating the pancreas to release bicarbonate ions, which neutralize the acid. This helps to maintain the pH balance in the small intestine and protect its delicate lining from the damaging effects of acid. Gastrin, on the other hand, stimulates the secretion of gastric acid, while cholecystokinin stimulates the release of digestive enzymes and bile.
39.
This hormone is stimulated by high levels of dietary fat in the small intestine.
Correct Answer
B. Cholecystokinin
Explanation
Cholecystokinin is the hormone that is stimulated by high levels of dietary fat in the small intestine. It is released by the cells in the lining of the small intestine in response to the presence of fat. Cholecystokinin plays a role in the digestion and absorption of dietary fat by stimulating the release of digestive enzymes from the pancreas and the contraction of the gallbladder to release bile. This hormone also helps to regulate appetite and promote feelings of fullness after a meal.
40.
This digestive aid, produced by the stomach, begins digestion by denaturing proteins.
Correct Answer
B. Hydrochloric acid
Explanation
Hydrochloric acid is the correct answer because it is produced by the stomach and plays a crucial role in the digestion process. It denatures proteins, breaking them down into smaller molecules that can be easily absorbed by the body. Without hydrochloric acid, proper digestion of proteins would not occur, leading to nutrient deficiencies and digestive issues. Bile, on the other hand, is produced by the liver and helps in the digestion of fats, while water does not have a significant role in the digestion of proteins.
41.
This structure regulates the flow of material into the colon.
Correct Answer
A. Ileocecal spHincter
Explanation
The ileocecal sphincter is responsible for regulating the flow of material from the small intestine into the colon. It acts as a valve, allowing the passage of digested food and waste into the large intestine while preventing backflow. This sphincter plays a crucial role in maintaining the proper functioning of the digestive system by controlling the movement of materials between these two sections of the gastrointestinal tract.
42.
Which of the following does is the primary function of the large intestine?
Correct Answer
C. Feces formation
Explanation
The primary function of the large intestine is to form feces. The large intestine absorbs water and electrolytes from the remaining undigested food material, which helps in consolidating the waste and forming solid feces. It also houses bacteria that aid in the final breakdown of any remaining nutrients and the production of certain vitamins. Chemical digestion primarily occurs in the small intestine, while absorption of nutrients occurs in both the small intestine and the large intestine.
43.
Chemical reactions that break down complex organic molecules into simpler ones are called:
Correct Answer
C. Catabolism
Explanation
Catabolism refers to the chemical reactions in which complex organic molecules are broken down into simpler ones. This process releases energy and is responsible for the breakdown of nutrients in our body to produce energy for various cellular activities. Unlike anabolism, which involves the synthesis of complex molecules from simpler ones, catabolism involves the opposite process. Therefore, catabolism is the correct answer to the question.
44.
Chemical reactions that combine simple molecules and monomers to form complex structures are known as
Correct Answer
B. Anabolism
Explanation
Anabolism refers to the chemical reactions in which simple molecules and monomers are combined to form complex structures. This process requires energy and is responsible for the growth and maintenance of cells and tissues. It is the opposite of catabolism, which involves the breakdown of complex molecules into simpler ones. Metabolism, on the other hand, encompasses both anabolism and catabolism, and refers to all the chemical reactions that occur in an organism to maintain life.
45.
When the terminal phosphate is cut off ATP what is formed?
Correct Answer
A. Adenosine dipHospHate
Explanation
When the terminal phosphate is cut off ATP, it forms Adenosine diphosphate (ADP). ATP is a molecule that stores and transfers energy in cells. When one of the phosphate groups is removed from ATP, it becomes ADP. This release of the phosphate group releases energy that can be used for various cellular processes. ADP can then be converted back to ATP through the addition of a phosphate group, thus replenishing the energy storage. GTP and Adenosine monophosphate (AMP) are different molecules and not formed when the terminal phosphate is cut off ATP.
46.
Oxidation is
Correct Answer
B. The removal of electrons
Explanation
In the context of chemistry, oxidation refers to the process of losing electrons. When a substance undergoes oxidation, it loses electrons, resulting in an increase in its oxidation state. This process is often accompanied by the addition of oxygen or the removal of hydrogen atoms. Therefore, the correct answer is "The removal of electrons."
47.
Reduction is the
Correct Answer
B. The addition of electrons
Explanation
The correct answer is "The addition of electrons." Reduction is a chemical reaction where electrons are gained, resulting in a decrease in the oxidation state of a molecule or atom. This process is typically accompanied by the addition of electrons to the reactant. The addition of protons does not accurately describe reduction, as it is the addition of electrons that leads to a reduction reaction.
48.
This is a derivative of vitamin B.
Correct Answer
A. NAD
Explanation
NAD is a derivative of vitamin B. It stands for Nicotinamide Adenine Dinucleotide and is involved in various metabolic processes in the body, particularly in energy production. NAD plays a crucial role in transferring electrons during cellular respiration and is essential for the conversion of nutrients into usable energy. It acts as a cofactor for many enzymes, facilitating important reactions in metabolism. Therefore, NAD being a derivative of vitamin B makes it an important component in maintaining overall health and proper functioning of the body.
49.
Which of the following is not a form of phosphorylation?
Correct Answer
A. Reduction pHospHorylation
Explanation
Reduction phosphorylation is not a form of phosphorylation because phosphorylation involves the addition of a phosphate group to a molecule, typically through the transfer of a phosphate group from ATP to the molecule. Reduction, on the other hand, involves the gain of electrons or the decrease in oxidation state of a molecule. Therefore, reduction phosphorylation is not a recognized process in cellular metabolism.
50.
Glycogenesis is NOT
Correct Answer
C. One way to make glycogen
Explanation
Glycogenesis is a process in which glucose molecules are converted into glycogen for storage. It is performed by hepatocytes, which are liver cells, and also by muscle fibers. Therefore, the statement "one way to make glycogen" is correct because glycogenesis is indeed one of the ways in which glycogen is produced.